# A line segment with endpoints at (5 , -9 ) and (2, -7 ) is rotated clockwise by pi/2. What are the new endpoints of the line segment?

The endpoints of the new line segment are $\left(9 , 5\right)$ and $\left(7 , 2\right)$.
Rotate each point $\frac{\pi}{2}$ radians, so I'll start with $\left(2 , - 7\right)$ because it's closer to the origin.
$\left(2 , - 7\right)$ becomes $\left(7 , 2\right)$
$\left(5 , - 9\right)$ becomes $\left(9 , 5\right)$