Question

Given f(x) = (x - 3)(x + 7), what are the x-intercepts?

Answer 1

We can easily say the x intercepts are +3 and -7

Or we can multiply (x-3) * (x+7)

x^2 + 4x -21 = 0

a = 1 b = 4 c = -21

We solve with the quadratic equation

x = 3

x = -7

So that proves our answers are correct.

Explanation: