Question

1. Triangle ABC with coordinate points A(-2,3); B(-1,0); C(5,-4) is rotated 90 degrees clockwise. What

are the new image points for triangle A'B'C'?

Answer 1

Answer: A'(3,2), B'(0,1) and C'(-4, -5).

Explanation:

When we rotate (a,b) 90 degrees clockwise, the new point will be (b,-a).

i.e. rotation rule for 90 degrees clockwise : (x,y) → (y,-x)

Given: Triangle ABC with coordinate points A(-2,3); B(-1,0); C(5,-4) is rotated 90 degrees clockwise.

Then, the new image points for triangle A'B'C' will be :

A(-2,3) → A'(3,-(-2)) =A'(3,2)

B(-1,0)→ B'(0,-(-1)) = B'(0,1)

C(5,-4) → C'(-4, -5)

Hence, the new image points for triangle A'B'C' are A'(3,2), B'(0,1) and C'(-4, -5).