Question

triangle abc was transformed using the rule (x, y)→(-y, x). the vertices of the triangles are shown. a(-1, 1) a(-1, -1) b(1, 1) b(-1, 1) c(1, 4) c(-4, 1) which best describes the transformation? the transformation was a 90° rotation about the origin. the transformation was a 180° rotation about the origin. the transformation was a 270° rotation about the origin. the transformation was a 360° rotation about the origin.

Explanation:

Step1: Recall rotation rules

The rule for a 90 - degree counter - clockwise rotation about the origin is $(x,y)\to(-y,x)$.

Step2: Check given rule

The given transformation rule is $(x,y)\to(-y,x)$, which matches the 90 - degree counter - clockwise rotation rule about the origin.

Answer:

The transformation was a 90° rotation about the origin.