Question

1. What is the excluded value for the rational expression x^2 - 4/3x - 6?

A: ?

2. The trinomial x ^2 - 6x + c is a perfect-square trinomial. What is the value of c?

A: 9

3. Find the positive solution of the equation x^2 + 5x - 4 = 0. Round your answer to the nearest tenth.

A: ?

4. What is the value of 4^0 - (2^-3)?

A: -7?

5. Identify the excluded value of y = x - 4/x - 2.

A: x = 2

6. Which of the following is equivalent to (2x^5y^2/ 8x)^-2?

a. 16/x^8y^4
b. x^8/16y^4
c. 4/x^4y^2
d. x^5/16

A: ?

Answer 1

#1 you cannot divide by zero. So, when the denominator is zero, that value of x must be excluded. So, what is x when 3x-6=0?

#2 ok

#3 use the quadratic formula for this one.

#4 Nope.
4^0 = 1
2^-3 = 1/2^3 = 1/8
So, 1 - 1/8 = 7/8
You calculated 4^0 - 2^3

#5 correct. So why did you have trouble with #1?

#6 since a^-n = 1/a^n, and 1/(a/b) = b/a,
(2x^5y^2/ 8x)^-2
= (x^4y^2/4)^-2
= 1/(x^4y^2/4)^2
= (4/(x^4y^2))^2
= 16/(x^8y^4)

Answer 2

1. x = 2?

3. 0.70 = 1 (rounded to the nearest tenth)?

Answer 3

#1 ok

#3 .701 = 0.7 to the nearest tenth. Your rounding doesn't have any tenths!