the rectangle below has an area of x^2 -x-72 square meters and a length of x + 8 meters. What expression represents the width of the rectangle?

Question

Factoring quadratics finds the roots or x-intercepts of a quadratic equation. Factoring quadratic equations in standard form, , can often be accomplished by finding two numbers that add to give b, and multiply to give ac. ... Find the roots by solving for ±x and substitute into the form .

Answer 1

b = -1

ac = -72

What are two factors of -72 that add up to -1? One is 8. The other must be -9.

x² - x - 72 = (x + 8)(x - 9)

The width is x - 9 meters.