Question

The area of a rectangle is 20. The length is 5, and the width is the √x. What is the value of x? What is the width of the rectangle?

A. The value of x is 4. The width is 16.
B. The value of x is 16. The width is 4 or –4.
C. The value of x is 4. The width is 2.
D. The value of x is 16. The width is 4.

Answer 1

Answer: D

Explanation:

A = LW

`√(x)` * 5 = 20

`(√(x) * 5)^(2) = 20^(2)` (square both sides)

x * 25 = 400

25x = 400

`(25x)/(25) = (400)/(25)` (divide both sides by 25)

x = 16

`√(16) = 4`

x = 16, and the width is 4.

Answer 2

D

Explanation:

5(
`√(x)`) = 20 Divide by 5

`√(x)` = 4 Square both sides

x = 16

Widths can't be negative