### Home > CAAC > Chapter 12 > Lesson 12.2.1 > Problem 12-40

12-40.

Find the equation of *f*(*x*) graphed below. Homework Help ✎

Identify all of the intercepts.

Write the equation as a factored quadratic since the two values of x are known.

y = (x - 3)(x + 1)

Make the equation negative because the parabola opens downward.

y = -(x - 3)(x + 1)

Use a generic rectangle to multiply the factors together. Distribute the negative.