# How do you write the function in standard form y=-7/3(x+6)(x+3)?

Aug 24, 2017

Is standard form y = $a {x}^{2} + b x + c$ for you, or is
it y = $a {\left(x - h\right)}^{2} + k$? I call the second equation "vertex" form.

#### Explanation:

So, take y = $- \frac{7}{3} \left(x + 6\right) \left(x + 3\right)$ and expand by multiplication:

y = $- \frac{7}{3} \left({x}^{2} + 9 x + 18\right)$

First, help with fractions: $- \frac{7}{3} \cdot 9 = - \frac{63}{3} = - 21$ and $- \frac{7}{3} \cdot 18 = - 7 \cdot 6 = - 42$.

Distribute: y = $- \frac{7}{3} {x}^{2} - 21 x + \left(- 42\right)$. This is what I call standard form.