# How do you solve 12t + 9 = 5t²?

Jun 17, 2016

$t = 3 \mathmr{and} t = - \frac{3}{5}$

#### Explanation:

Make the quadratic equal to 0.

$5 {t}^{2} - 12 t - 9 = 0$

$\left(5 t + 3\right) \left(t - 3\right) = 0 \text{ factorise}$

$5 t + 3 = 0 \Rightarrow 5 t = - 3 \Rightarrow t = - \frac{3}{5}$
$t - 3 = 0 \Rightarrow t = 3$