8th Grade Math Lesson 2-10 Practice

Vocabulary Terms Define/Illustrate
1. Formula
2. Rearrange an equation
3. Variables

Problems: Show all work: Solve for each of the formulas for the indicated variable(s)
4. P=2L+2W for W
5. AX+B=0 for X
6.V+LWH for H
7. Y=MX+B for X
8. If the perimeter of a rectangle is 60ft and its length is 18ft, find its width. (see formula in number 1)

1 answer

1. Formula: A mathematical equation or relationship that expresses a rule or principle. (illustration: E = mc^2, where E represents energy, m represents mass, and c represents the speed of light)
2. Rearrange an equation: To manipulate an equation to isolate a specific variable or term. (illustration: rearranging the equation 2x + 3 = 7 to solve for x by subtracting 3 from both sides and then dividing by 2)
3. Variables: Symbols used to represent unknown values or quantities in mathematical expressions or equations. (illustration: x, y, a, b, etc.)

4. P = 2L + 2W for W:
To solve for W, we need to isolate it on one side of the equation:
P - 2L = 2W
Divide both sides by 2 to solve for W:
(P - 2L) / 2 = W

5. AX + B = 0 for X:
To solve for X, we need to isolate it on one side of the equation:
AX = -B
Divide both sides by A to solve for X:
X = -B/A

6. V + LWH for H:
To solve for H, we need to isolate it on one side of the equation:
LWH = H - V
Divide both sides by LW to solve for H:
H = (LWH - V) / LW

7. Y = MX + B for X:
To solve for X, we need to isolate it on one side of the equation:
MX = Y - B
Divide both sides by M to solve for X:
X = (Y - B) / M

8. If the perimeter of a rectangle is 60ft and its length is 18ft, find its width:
The formula for the perimeter of a rectangle is P = 2L + 2W.
We are given that the perimeter is 60ft and the length is 18ft, so we can substitute those values into the formula:
60 = 2(18) + 2W
Simplify and solve for W:
60 = 36 + 2W
Subtract 36 from both sides:
24 = 2W
Divide both sides by 2 to solve for W:
W = 12ft