Question

The function f(x) = x + 5 represents the length of a rectangle, and the function g(x) = 7x − 2 represents the width of the rectangle. What is the area of the rectangle if x = 3?

a. 56

b. 27

c. 285

d. 152

Answer 1

Answer = d. 152

Given
x = 3
L = x + 5
W = 7x -2

Area formula = L x W

Substitute values of L and W

Area = (x + 5) * ( 7x -2)

Substitute value of x = 3 in for x

Area = ( 3 + 5) * ( 7*3 - 2)
Simplify

Area = 8 * (21 - 2)

Area = 8 * 19

Area = 152 units squared