# How do you solve using completing the square method x^2 + 2x-7=0?

Jul 1, 2016

When completing the square, you're turning

$a {x}^{2} + b x + c = 0$

into

$a {\left(x + d\right)}^{2} + e = 0$

Obtaining $a$ is easy. It's the coefficient of the first term.
To solve for d, use this formula:

$d = \frac{b}{2 a}$

Finally, to solve for e use this formula:

$e = c - {b}^{2} / \left(4 a\right)$