# How do you write in standard form y = (x - 1)(5x + 2)?

Jun 24, 2015

Standard form: $y = 5 {x}^{2} - 3 x - 2$

#### Explanation:

Standard form for a quadratic is
$\textcolor{w h i t e}{\text{XXXX}}$$y = a {x}^{2} + b x + c$ for constants $a , b , \mathmr{and} c$

Multiplying $\left(\textcolor{red}{x} \textcolor{b l u e}{- 1}\right) \left(5 x + 2\right)$
as $\textcolor{red}{\left(x\right)} \left(5 x + 2\right) \textcolor{b l u e}{- 1} \left(5 x + 2\right)$
$= \textcolor{red}{5 {x}^{2} + 2 x} \textcolor{b l u e}{- 5 x - 2}$
$= 5 {x}^{2} - 3 x - 2$
allows us to rewrite the equation in this standard form.