Question

Determine which factors below can be the dimensions of a rectangle with an area of .

Answer 1

B

Explanation:

Area of a rectangle is length * width.

The question asks which of the following (length * width) will give the expression for area...

We multiply each, and whichever is equal to the expression for area given, is the answer. We use the distributive property to expand.

Distributive property is
`a(b+c)=ab+ac`

A.

`(3x-7)(4x+9)\\=12x^2+27x-28x-63\\=12x^2-x-63`

This is not the answer.

B.

`(3x+7)(4x-9)\\=12x^2-27x+28x-63\\=12x^2+x-63`

We don't need to do more because B is equal to the expression of area given.

B is the correct answer.