Question

The area of a square is represented by 9x2 - 42x + 49. Find the length of each side.

O (9x-7)
O (3x-7)(3x+7)
O (3x-7)
O (3x+7)
O cannot be determined

Answer 1

3x-7

Explanation:

A square’s area represents (ax+b)^2. Let’s expand that.
`a^2x^2+2abx+b^2` now, we can notice this fits perfectly when a=3 and b=-7. Therefore one side length of the square is 3x-7.