Question

The function f(x) =4x+3 represents the length of a rectangle. The function g(x)=2x-5 represents the width of the rectangle.Use (f•g)(4) to determine the area of a rectangle

Answer 1

Answer: 57 square units.

Explanation:

Given : The function
`f(x) =4x+3` represents the length of a rectangle.

The function
`g(x)=2x-5` represents the width of the rectangle.

Then , the area of the rectangle is given by :_

`A=(f\cdot g)(x)=f(x)\cdot g(x)\\\\=(4x+3)(2x-5)`

At x= 4,

`A=(f\cdot g)(4)=(4(4)+3)(2(4)-5)\\\\=(16+3)(8-5)=19*3=57`

Hence, the area of a rectangle = 57 square units.