# How do you factor the expression 36y^2-84y-147?

Mar 2, 2016

$\textcolor{b l u e}{y = 3.49 \text{ or } y = - 1.16}$ to 2 decimal places

$\left(y - 3.49\right) \text{ and } \left(y + 1.16\right)$

#### Explanation:

Treating this the same way you would as a quadratic $x$

Given:$\text{ } x = 36 {y}^{2} - 84 y - 147$

Where:$\text{ } y = \frac{- b \pm \sqrt{{b}^{2} - 4 a c}}{2 a}$

$a = 36$
$b = \left(- 84\right)$
$c = \left(- 146\right)$

Then:$\text{ } y = \frac{+ 84 \pm \sqrt{{\left(- 84\right)}^{2} - 4 \left(36\right) \left(- 146\right)}}{2 \left(36\right)}$

$y = \frac{84 \pm \sqrt{7056 + 21024}}{72}$

$\textcolor{b l u e}{y = 3.49 \text{ or } y = - 1.16}$ to 2 decimal places