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I would like to know how many of the people answering math questions here are current math teachers, were math teachers at one time, are current tutors working for a tutoring company or simply love math. What's your story? I would love to hear from all ma...

17 years ago

Those of us who love math certainly know two basic facts about Mr. Gottfried Wilhelm Leibniz: (1) He and Newton (our calculus guy) did not get along AND (2) Mr. Leibniz was a self-taught mathematician My question is for all tutors here who love math. What...

17 years ago

I think a good math teacher is someone who can explain math topics at the level of students. A good math teacher is someone who does not try to impress students with his or her math skills (college math professors are famous for boasting). In your opinion...

17 years ago

I was wondering how sub teachers survive during the long summer months when there is no pay, especially if you live alone and must pay rent. If you are a sub who lives alone, what plans do you have for YOUR future, financially speaking? Do you save money...

17 years ago

How many sub teachers can really say that they are happy working as a sub teacher? Look deep inside and honestly answer the question: Are You Happy Subbing?

17 years ago

What we have here is a question from Statistics called Permutations. A permutation is an ordered arrangement of r objects chosen from n objects. Solution: 5 shirts x 6 slacks x 7 ties = 210 outfits can be made.

17 years ago

You can graph just about any equation on the xy-plane. You need to know the values for the x and y coordinates in the form (x,y). The easiest way to graph any equation in algebra is to make a table. Basically, you will plug a bunch of numbers for x (say a...

17 years ago

You were given two questions: Find the area of each circle use 22/7 for pie. 1. r=14ft 2.d=3 1/3 yd First of all, it's not pie; it's pi. Pie is something we eat; pi is an irrational number. The symbol for pi is ð. The area of a circle formula is: Area = p...

17 years ago

You were given: Find the derivative of f 0f x. f(x) = x^2 - 8x - 17 at x = 4 We first find the derivative of the given function and then replace x with 4 in the derivative we will find. I will use the power rule to find the derivative of your function. Th...

17 years ago

Hello. We have an inequality question here. We have: -38 > t - 46....This is read: "negative 38 is greater than the value of t minus negative 46." We need to find a number that is bigger than t without revealing what t will be. To find the value of t, add...

17 years ago

You were given: A rectangle has a width that is 1/8 its length. If the perimeter of the rectangle is 126 inches, what is the width of the rectangle? Length = we don't know and so I'll call it x. Width = 1/8(x), which can be written x/8. The perimeter give...

17 years ago

Your set up is correct. I will replace ? with x and solve for x. 5/8 = x/40 We now cross-multiply. 8 times x = 8x. 5 times 40 = 200 We now have: 8x = 200 To find x, we divide both sides of the equation by 8. x = 200/8 x = 25 What is the same fraction as 5...

17 years ago

What is a fraction? part/whole = fraction 10/15 = fraction 5 into 10 = 2 (our numerator) 5 into 15 = 3 (our denominator) Final answer: 2/3 Done!

17 years ago

Rearrange the numerator to become (-x^2 + 4x - 3)/(x - 1) Factor the numerator. The numerator becomes -x^2 + 3x + x - 3. We divide the numerator's polynomial into two groups: (-x^2 + 3x) is group a. (x - 3) is group b. We factor group a. We cannot factor...

17 years ago

Yes, Reiny answer's is correct. I went back to redo the question and got the same answer as Reiny. Sorry for the mistake.

17 years ago

Your question: The Occupational Safety and health Administration (OSHA) estblished permissible sound exposures in the work-place. This is modeled by the equation: S = -2.817H + 108.9 Use the formula for the problem: S = maximun permissible sound level in...

17 years ago

Use the distance formula for finding points on the xy-plane. Let d = distance. d = sqrt{(x2 - x1)^2 + (y2 - y1)^2} You must apply the above formula to find the distance between points A and B, B and C and A and C. So, you must apply the distance formula 3...

17 years ago

Use the distance formula: distance = rate times time or in short D = rt. Set up a chart and then use the formula. Got it? If not, write back.

17 years ago

There is missing data here. Is 30 the hypotenuse or one of the legs of the right triangle? The same for 34. There is no way for me to know if BC is one the legs or is BA is the hypotenuse or vice-versa. Once I know that, I can proceed to help you.

17 years ago

I will give you the cube root and you can do the rest. The cube root is a number that when multiplied 3 times by itself will yield 5832, in this case. The cube root is 18. Why 18? Because 18 x 18 x 18 = 5832. You finish the question.

17 years ago

Multiply 7 times the given number of inches. I will first convert 1_1/16 to an improper fraction. So, 1_1/16 becomes 17/16. We can multiply 7 times 17/16 a lot easier. Then: 7 x 17/16 = 7_7/16 is the distance. Done!

17 years ago

We use the Pythagorean Theorem to find length AC as step 1. In other words, we MUST find the ADJACENT LEG. AC^2 + BC^2 = BA^2 AC^2 + (30)^2 = (34)^2 AC^2 900 = 1156 AC^2 = 1156 - 900 AC^2 = 256 We now take the square root of both sides of the equation to...

17 years ago

Rise is always divided by the run. Rise/Run is what you must use. However, the rise is 96 inches in this case and the run is 32 inches. So, our fraction should be 96/32 = 3. However, 3 is a whole number not a fraction. Is there a typo here? Shouldn't the...

17 years ago

I will solve one of the questions only. A computer can execute 64 instructions per second. How many instructions can it execute in 10 minutes? Let x = the number of instructions in 10 minutes. We use the following proportion: 64 instructions/x instruction...

17 years ago

Multiply the numerators and denominators across. Then simplify your fraction to the lowest term. 31/6 x 9/11 x 6/17 = 31 x 9 x 6 = 1674 (our numerator product) 6 x 11 x 17 = 1122 (our denominator product) We now have: 1674/1122 as the new fraction. When r...

17 years ago

For question 1, we need a trig function that equals opposite over hypotenuse. Which one? Tangent = OPP/HYP To find x we use CHOICE (C). ============================ For question 2, we are looking for angle A. We use tan(A) = OPP/HYP tan(A) = 15/26 Since w...

17 years ago

Jon, I made a mistake. Sorry! sine = OPP/HYP NOT tangent. It was a simple mistake. Damon got it right. Thanks, Damon!

17 years ago

Basically to see if the value found for x will yield the same answer on both sides of the equation.

17 years ago

We use the formula: M = P( 1 + i )^n M is the final amount including the principal. P is the principal amount. i is the rate of interest per year. n is the number of years invested. M = 4624 P = 3400 n = 8 years We seek i. 4624 = 3400(1 + i)^8 You do the...

17 years ago

Multiplication facts: 2 x 9 means two rows times 9 columns. Facts: 2 x 9 = 18 18/2 = 9 18/9 = 2 9 x 2 = 18 Do the same with the other other numbers. Also, note that 2 and 9 are factors of 18 and 18 itself is the product of 2 and 9.

17 years ago

This question must have a typo. Do you mean 2% times 734? OR Do you mean break down 2/734 to the lowest term? To reduce 2/734, we divide 2 into itself and into 734. If we do that, this is what the new fraction becomes: 1/367 However, if you want to multip...

17 years ago

Your question is not too clearly typed. 1_3/4 times 2_5/8 indicates that we are dealing with a rectangle where the length is the bigger length and the width is the shorter length. 2_5/8 when expressed an an improper fraction becomes 21/8 and 1_3/4 becomes...

17 years ago

Which fraction is bigger: 4_5/8 or 3_1/2? 4_5/8, right? We are given that 1/4 = 1 foot, right? Divide 4_5/8 by the given scale or 1/4. 4_5/8 divided by 1/4 = 18_1/2 feet for the longest side.

17 years ago

4 feet = 12 inches times 4 = 48 inches. 48 inches divided by 5/8 inches = 76_4/5 inches.

17 years ago

You did not say exactly what you need done. I assume you are trying to divide, right? Divide the trinomial by the binomial. You can use synthetic division to solve this question more easily. If you get stuck, let me know.

17 years ago

Use synthetic Division to solve more easily. You can search online for a website that explains synthetic division.

17 years ago

Well, y is the same as f(x). In other words, y = f(x) and f(x) = y because they are interchangeable. For example, y = x + 5 is the same as if you were to write it f(x) = x + 5. Did you know that? Do you see f(0)? It tells you to replace x with 0 everywher...

17 years ago

Set the equation to 0 and solve for x. 2x^2 = 200 Divide both sides by 2. x^2 = 200/2 x^2 = 100 Take square root of both sides. x = positive 10 and negative 10 Always a positive and negative answer in terms of square roots. Done!

17 years ago

We have a difference of cubes. Did you apply the formula given by Reiny? If you did, there should be no more doubts. A^3 - 27 = difference of cubes. First, write 27 as an exponent. What number when multiplied by itself 3 times will yield 27? How about 3?...

17 years ago

I will do number 2 only. We have this: (x-3)^2 = -4 The left side becomes x^2 - 6x + 9. We now have this: x^2 - 6x + 9 = -4 Add 4 to both sides and then equate to zero. x^2 - 6x + 9 + 4 = 0 x^2 - 6x + 13 = 0 This quadratic equation cannot be solved by fac...

17 years ago

Ms. Sue gave you the formulas. Did you apply the formulas? A = 3.14 (r)^2 A = 3.14 (2.5)^2 A = 3.14 (6.25) A = 19.625 ================== C = 2 (3.14)(2.5) C = 15.7 Done!

17 years ago

diameter = 2 times radius In other words, it takes 2 radii to make one diameter. You are given the diameter to be 8 inches. We have: 8 inches = 2r We divide both sides of the equation by 2 to find r. 8 inches/2 = r 4 inches = r Let r = radius. Then, radiu...

17 years ago

We add all the numbers given. 132 + 145 + 140 + 128 = 545 You were given 4 THREE-DIGIT numbers. The sum is 545. We now divide 545 by 4. Average = 545/4 Average = 136.25

17 years ago

Total = 1500 x 0.05 + 1500 Let t = total t = 1500 x 0.05 + 1500 t = 75 + 1500 t = $1575 Done!

17 years ago

2/3 + 4/6 Find the LCD. The LCD is 6 because it is the smallest number that both denominators given fit into without a remainder. LCD = 6. We now divide the LCD by each denominator and then multiply the quotient by each numerator. 6 divided by 3 = 2 2 x 2...

17 years ago

V = 3^3 V = 27inches^3 Volume is always measured in cubic inches, feet, yards, etc. Done!

17 years ago

This is a scalene triangle. P = side + side + side P = 6 inches + 8 inches + 10 inches P = 14 inches + 10 inches P = 24 inches Done!

17 years ago

Area = length TIMES width or in short A = LW ====================================== A = 10 x 12 A = 120feet^2 NOTE: Area is always measured in squared units. Done!

17 years ago

I think you meant to type: (-35 + 7w)/5 divided by (121w - 605)/25 We have a complex fraction here. We invert (121w - 605)/25 to become 25/(121w - 605) and then we multiply by the left side fraction just like you did back in grammar school We now have thi...

17 years ago

We have this: 7/9z^3 + 1/21z^3 Our LCD is 63z^3. We now divide the LCD by each denominator and then multiply the quotient by each numerator. 63z^3/9z^3 = 7 Then, 7 times 7 = 49 ===================== Next fraction: 63z^3 divided by 21z^3 = 3 Then, 3 x 1 =...

17 years ago

fraction = part/whole fraction = 16/20 fraction = 4/5 Done!

17 years ago

Machine will: *double any amount placed inside *add $5 to the amount that is doubled *a total of $51 was the end result Let x = how much money he first placed in the box. Let 2x = the double amount 2x + 5 = 51 2x = 51 - 5 2x = 46 x = 46/2 x = $23 Done!

17 years ago

We have this: 6/(x+b) - 6/(x-b) Our LCD is (x + b)(x - b) We divide the LCD by each denominator and then multiply the quotient by each numerator. (x + b)(x - b) divided by (x + b) = (x - b) Then, 6 times (x - b) = 6x - 6b. ===============================...

17 years ago

Decimal Place Values: Tenths Hundredths Thousandths Ten thousandths Hundred Thousandths Millionths Notice that all end with the same three letters "ths." See it? Decimals are located to the right of the decimal point. All numbers to the left of the decima...

17 years ago

Why not cross-multiply? 9 times w = 9w 8 times (w - 12) = 8w - 96 We now equate 9w and 8w - 96 and solve for w. 9w = 8w - 96 9w - 8w = -96 w = -96....This is our solution. ================================ To check, replace w with -96 in the original fract...

17 years ago

Becky, I am sorry. I did not see that w subtracts the fraction 1/2 NOT 12. So, Jas is correct. Sorry for the error. Done!

17 years ago

The answer is A.

17 years ago

To complete drwls' answer: 12 x 24 = 288 for Judy Done!

17 years ago

This question is incomplete. Where are the numbers?

17 years ago

175% must be changed to a decimal number before doing anything else. So, 175% becomes 1.75 Let x = what number Then, 1.75(x) = 50 To find x, we divide both sides of the equation by 1.75. x = 50/1.75 x = 28.57 Done!

17 years ago

Try the formula: V = base times height V = 40 x 30 Can you finish?

17 years ago

You know it is impossible to graph anything using a keyboard. Do this: 1-Isolate y for both equations. 2-Select about 3 values for x and solve for y in both equations. 3-Then graph the points that you find on the xy-plane. 4-Connect the points with a soli...

17 years ago

LCM = 30a^6b^8

17 years ago

Question 2 has a typo. Rewrite question 2 because it does not make sense. Question 1: Find the greatest common factor in this problem. 12a^3b^2, 18a^2b^3, 6a^4b^4 GCF = 36a^4b^4 Done!

17 years ago

No question here. Rewrite, please.

17 years ago

The word of means MULTIPLY. 5% becomes a decimal: 0.05 We now multiply: 0.05 x 45,000 = 2250 Done!

17 years ago

Are you studying for a trig test? Just curious! Where is your effort? Why do you not try to solve each question and show your work? Then we can help you better. I would like to know if you are preparing for a math state test.

17 years ago

We have this: How do you use the substitution method to solve the linear system? -2x - 5y = 7...Equation A 7x - y = -8...Equation B The idea is to isolate y OR x (your choice) and then plug that into EITHER Equation A or B (your choice). I will isolate y...

17 years ago

Thank you for being honest. I don't mind helping you when there is time. However, I will only solve one or two questions and allow others to do the rest.

17 years ago

You are referring to the discriminant, which is part of the quadratic formula in the RADICAND section. Here is how the discriminant works: Given a quadratic equation in the forn ax^2 + bx + c = 0, plug the coefficients into the expression b^2 - 4ac to see...

17 years ago

7 girls x 2 legs per girl = 14 legs. 7 girls x 7 backpacks = 49 backbacks. 49 backpacks x 7 big dogs = 343 big dogs 343 big dogs x 4 legs per dog = 1372 legs 343 big dogs x 7 puppies = 2401 pupies 2401 puppies x 4 legs per puppy = 9604 legs Total legs = 9...

17 years ago

We have this: The floor areas of a living room on a house plan measures 3_1/2 inches by 4_ 5/8 inches. If the scale is 1/4 inch = 1 foot, find the length of the longest side of room in feet. Multiply the given inches. 3_1/2 times 4_5/8 = 16_3/16 The quest...

17 years ago

There are many definitions of rate depending on the branch and math question.

17 years ago

7_3/8 = original board size The orginal board is cut to 3/4 of its original size. The word [of] means multiply. Therefore, 7_3/8 x 3/4 = ???

17 years ago

Your question does not make sense. Please, retype your question correctly.

17 years ago

A Permutation is an ordered Combination. There are basically two types of permutation: 1-Repetition is Allowed. 2-No Repetition is allowed. Your question is one without repetition. To answer, multiply 50 x 49 x 48 =??? Why did I stop at 48? Because the qu...

17 years ago

We have this equation: 8 - 9t = 21t - 17 We need to find t. This is called solving for t. We first combine like terms. -9t - 21t = -8 - 17 Do you see what I did? I placed all numbers with the letter t on the left side of the equation and all the constants...

17 years ago

Whenever you read a math question asking how many different arrangements are possible, you simply MULTIPLY what has been given. In this case, 8 students x 8 desks = 64 possible arrangements. Done!

17 years ago

62g=17h 258p=89g w=92.95 h=0.06 Since each ox horn is 6 cents, each green stone would equal 51/31 cents after plugged into equation (1). Then divide 92.95 by 51/31 to get approximately 5649.9 or 5650 green stones. Is that right?

17 years ago

Yes. Why? Original board = 7_3/8 inches, right? You cut 3/4 of its size (its size is 7_3/8 inches). The board is now 177/32 inches or as a mixed number 5_17/32 inches, which is 3/4 smaller than 7_3/8 inches (the original size of the board). Got it?

17 years ago

One square foot = 12 inches x 12 inches, which is 144 inches. Then, 36 square feet x 144 inches = 5184 inches. ============================= One square yard = 3 feet x 3 feet One foot = 12 inches. 12 inches x 3 feet = 36 inches. Then 36 inches x 36 inches...

17 years ago

My friend if you don't care about your own math work, then no one else will, too. Math rules!

17 years ago

This is no math question!

17 years ago

You are given the volume to be 5 inches times 10 inches times 7 inches, which = 350 inches^3. Volume in measured in cubic units, which is the reason for exponent 3. You are NOT too clear with the scale given as 1 inch = 6 inches. Do you want to convert to...

17 years ago

We have this: (3) Simplify: -5(cot^2theta-csc^2theta) A)5 B)-5 C)-5csc^2 theta D)5csc^2 theta I chose A You said B, right? Let's see if that's true. I will use x in place of theta to avoid having to write the word theta through and through. So, x = theta....

17 years ago

(1) A triangle is called an isosceles triangle if it has two sides with equal lengths. Consider an isosceles triangle ABC with AC = CB. Then side AB (i.e. the side that is not equal to the other sides) is called the base side. The angle opposite the base...

17 years ago

Below is a typical ellipse equation. [(x - 6)^2]/9 + [( y + 4)^2]/25 = 1 Do you see the denominators 9 and 25? If you take the square root of each denominator, what is the biggest and smallest result? The square root of 9 = 3. The square root of 25 = 5. F...

17 years ago

Make sense to me. Good job!

17 years ago

What about a square with one side equal to 4 feet? All sides of a square are the same length and so, the perimeter = 16 feet. What about an scalene triangle? A scalene triangle does not have the same length on all 3 sides. You can use a scalene triangle w...

17 years ago

Completing the square is not the easiest way to solve quadratic equations; its strength lies in the fact that the process is repetitive and predictable. Here is the best news: completing the square ALWAYS (SAY ALWAYS) will work, unlike the factoring metho...

17 years ago

I will try question 1. We need to use the correct Half-Angle Formula to find the exact value of cos105 degrees without using a calculator. Because 105 degrees = cos(210)/2, we can use the Half-Angle Formula for cos(x)/2 with x = 210 degrees. Also, because...

17 years ago

Reiny said: "The same applies to cos 210 in the third quadrant." When we deal with Half-Angle Formulas, the sign selected to be placed in front of the square root has to do with the ORIGINAL degree given. He was given cos105 degrees (in quadrant 2) not 21...

17 years ago

This is more medical conversion factors than mathematics. Try placing your question in the science section. The medical terms does not make the conversion factor easy to play with.

17 years ago

Let any letter of the alphabet = what you spend on the project. Follow what Reiny said.

17 years ago

I apologize. I though you were talking about question 1. Sorry mate....

17 years ago

I see. WOW! High school teacher for 35 years. That is truly amazing! Believe it or not, I learned high school math through textbooks/video tapes and answering questions online. I have two college degrees in areas other than math. However, I was an excelle...

17 years ago

What an interesting reply. I must be the only person here answering questions just for the love of math without having an actual teaching certificate in mathematics. You are a professor, right? I really loved my math professors back in college. I was a so...

17 years ago

You may not have actual teaching experience but you are a professional nonetheless. I was an excellent math student back in my pre-college and college years but never taught math in my own classroom except as a substitute teacher. Sub teaching is more lik...

17 years ago

Another professional here. Honestly, I must be the only unprofessional person answering math questions in this and other forums. I am a substitute teacher (baby-sitter) and weekend security guard (both part-time jobs). So far, the replies have been great...

17 years ago

I will set it up for you and you can simplify. A = 42 h = 7 b2 = 9 I will plug and you can chug. 42 = 1/2(b1 + 9)(7) Solve for b1, which is read "b sub one." Can you take it from here?

17 years ago

Here it is: First multiply 7 x 1/2 = 7/2. We now have this equation: 42 = 7/2(b1) + 9) Simplify the right side of the equation and the whole thing becomes 42 = 7/2(b1) + 63/2 Subtract 63/2 from 42. 42 - 63/2 = 10_1/2 We now have: 10_1/2 = 7/2(b1) 10_1/2 d...

17 years ago

Use a trig function that states opposite/hypotenuse. Of course, this would be the sine function. sin(45degrees) = h/7meters Let h = height of building sin45 = h/7 sin45 times 7 = h 4.949747468 = h Round 4.949747468 to the nearest tenths becomes 4.95 meter...

17 years ago

What equation? Where is the equation?

17 years ago

This question is incomplete.

17 years ago

The mode is the number that is listed the most. You can see that 9 appears more than the rest of the numbers. Then, 9 is the mode.

17 years ago