Question

sat/act a point is rotated 270° about the origin. the image of the point is (-11, 7). what are the coordinates of the preimage? ① (7, -11) ② (-7, -11) ③ (7, 11) ④ (11, 7)

Explanation:

Step1: Recall 270° rotation rule

A 270° rotation about origin transforms preimage $(x,y)$ to image $(y,-x)$.

Step2: Set up equation for image

Let preimage be $(x,y)$. Image is $(y,-x)=(-11,7)$.

Step3: Solve for x and y

From $y=-11$ and $-x=7$ → $x=-7$. So preimage is $(-7,-11)$.

Answer:

B. (-7,-11)