# A machinist creates a washer by drilling a hole through the center of a circular piece of metal. If the piece of metal has a radius of x + 10 and the hole has a radius of x + 6, what is the area of the washer?

Aug 9, 2016

$= 8 \pi \left(x + 8\right)$

#### Explanation:

Area of the Circle$= \pi {r}^{2}$
Area of the washer
$= \pi \left({\left(x + 10\right)}^{2} - {\left(x + 6\right)}^{2}\right)$
$= \pi \left(x + 10 + x + 6\right) \left(x + 10 - x - 6\right)$
$= \pi \left(2 x + 16\right) \left(10 - 6\right)$
$= 8 \pi \left(x + 8\right)$