# How do you evaluate xy - z, when x = 3, y = 5 and z = -7?

Apr 13, 2018

#### Answer:

$22$

#### Explanation:

Just plug in all the values to the expression

$x y - z$

$\left(3\right) \left(5\right) - \left(- 7\right)$

$15 - \left(- 7\right)$

When you subtract a negative it's the same thing as adding. So if there is a double negative you add.

$15 + 7$

$22$

Answer:

$22$