Question

1. what is the result of rotating the point (1, 2) 90 degrees counterclockwise around the origin?

a. (2, -1)
b. (-2, -1)
c. (-1, -2)
d. (-2, 1)

Explanation:

Step1: Recall 90° CCW rotation rule

For a point $(x,y)$, rotating 90 degrees counterclockwise around the origin transforms it to $(-y,x)$.

Step2: Substitute $(1,2)$ into the rule

Let $x=1$, $y=2$. The new coordinates are $(-2, 1)$.

Answer:

d. $(-2,1)$