# How do you find the zeros by rewriting the function h(x)=x^2-4x-77 in intercept form?

Oct 15, 2017

You may factorize.

#### Explanation:

After some trying you will find that:
$= \left(x - 11\right) \left(x + 7\right)$ fits the bill, because:
$- 77 = \left(+ 7\right) \times \left(- 11\right)$ and $- 4 = - 11 + 7$
This is called the product-sum method.

So the zeros are:
$x = + 11 \mathmr{and} x = - 7$