Question

The length of a rectangle is 5 centimeters less than 2 times the width.

a. Write a polynomial expression that represents ( 2 points )
the area of the rectangle. Simplify the expression.

Find the area of the rectangle when width is 10 centimeters.

Answer 1

A = 2w² - 5w

150 sq.cm

Explanation:

Let the length be L and width be w

If the length of a rectangle is 5 centimeters less than 2 times the width, then;

L = 2w - 5

Area of the rectangle A = Lw

Since L = 2w - 5

A = (2w-5)w

Expand

A = 2w² - 5w

b) if w = 10cm

A = 2w² - 5w

A = 2(10)² - 5(10)

A = 200 - 50

A = 150 sq.cm

Hence the required area is 150 sq.cm