# What is the standard form of  y= (x-6) (x-3) ?

Feb 7, 2016

Multiply out to find:

$y = {x}^{2} - 9 x + 18$

#### Explanation:

We can use the FOIL mnemonic to help multiply this out:

$y = \left(x - 6\right) \left(x - 3\right)$

$= \stackrel{\text{First" overbrace(x*x) + stackrel "Outside" overbrace(x*(-3)) + stackrel "Inside" overbrace((-6)*x) + stackrel "Last}}{\overbrace{\left(- 6\right) \left(- 3\right)}}$

$= {x}^{2} - 3 x - 6 x + 18$

$= {x}^{2} - 9 x + 18$

This is in standard form with the powers of $x$ in descending order.