Question

rotations
find c after $r_{90^{\circ}}(x,y)=(-y,x)$.
$c = (?, )$

Explanation:

Step1: Identify coordinates of C

From the grid, $C=(8,9)$

Step2: Apply rotation formula

Use $r_{90^\circ}(x,y)=(-y,x)$. Substitute $x=8,y=9$:
$(-9,8)$

Answer:

$(-9, 8)$