Question

timed problem
score: 0/10 current time: 0.9
rotation 90° counterclockwise around the origin of the point (9, 2)
answer
(-2, -9)
(2, 9)
(9, -2)
(-2, 9)

Explanation:

Step1: Recall rotation rule

The rule for rotating a point $(x,y)$ 90° counter - clockwise around the origin is $(x,y)\to(-y,x)$.

Step2: Apply the rule

For the point $(9,2)$, when we apply the rule, $x = 9$ and $y = 2$. So, $-y=-2$ and $x = 9$. The new point is $(-2,9)$.

Answer:

D. $(-2,9)$