Question

the length of a rectangle is 8 centimeters less than 3 times the width. write a polynomial that represents the area of the rectangle. find the area of the rectangle when the width is 10 centimeters.

Answer 1

`A=3w^2-8w`

When w=10 then A=220 square cm

Explanation:

To calculate an area of a rectangle, use the formula A=l*w. We know the length is 8cm less than 3 times the width. So l = 3w - 8.

So the area is
`A= (3w - 8)*w = 3w^2-8w`

If the width is 10 then substitute w=10 into the polynmial.

`A= 3w^2-8w\\A=3(10)^2-8(10)\\A=300-80\\A=220`