Question

What are the `x`-intercepts of the graph of the function `f(x) = x^2+4x-12`?

Answer 1

2 and -6

Explanation:

The 2 x-intercepts are the 2 real roots of the quadratic equation:
`y = x^2 + 4x - 12 = 0.`
To solve it, find 2 numbers (real roots) having as sum (-b = -4) and as product (c = -12). The 2 roots have opposite signs since ac < 0.
The 2 real roots are : 2 and -6. (Product: -12. Sum = -4)