Question

m (3, −6) is rotated 90° counterclockwise.
(x, y) → (−y, x)
1 switch the x- and y-coordinates:
(6, −3)
2 multiply the new x-coordinate by −1:
(6(−1), −3)
3 simplify:
(−6, −3)
mary beth used the mapping rule to find the coordinates of a point that had been rotated 90° counterclockwise around the origin.
examine the steps to determine whether she made an error.
the student m
an error in step 1
an error in step 2
an error in step 3
no error

Explanation:

Step1: Verify Step 1 of work

Original point: $(3, -6)$. Switching $x,y$ gives $(-6, 3)$, but Mary Beth wrote $(6, -3)$. This is incorrect.

Step2: Confirm rule application

The rule $(x,y)\to(-y,x)$ means first take $-y$: $-(-6)=6$, then use original $x=3$. Correct result is $(6, 3)$. Mary Beth switched coordinates incorrectly in Step1.

Answer:

an error in step 1