# How do you multiply (x + -3)(10x + -20)?

Aug 8, 2017

$10 {x}^{2} - 50 x + 60$

#### Explanation:

$\left(x + - 3\right) \left(10 x + - 20\right)$

$=$ $\left(x - 3\right) \left(10 x - 20\right)$

$=$ $x \cdot \left(10 x - 20\right) - 3 \cdot \left(10 x - 20\right)$

$=$ $\left(10 {x}^{2} - 20 x\right) - 30 x + 60$

$=$ $10 {x}^{2} - 20 x - 30 x + 60$

$=$ $10 {x}^{2} - 50 x + 60$