Question

The vertices of a triangle are A(2,5) B(1,2) and C(3,1). Find the coordinates of the image after a rotation 90° clockwise about the origin.

Answer 1

A’ (5,2) B’ (2,1) and C’ (1,3)

Explanation:

When we reflect a point (x,y) over x-axis, we get (x,-y)

A ( 2,5) becomes (2,-5)

B (1,2) becomes (1,-2)

C ( 3,1) becomes (3,-1)

Then we proceed to rotate 90 degrees counterclockwise about the origin

(x,y) becomes (-y,x)

(2,-5) becomes (5,2)

(1,-2) becomes (2,1)

(3,-1) becomes (1,3)