Question

Rectangle PQRS is rotated 90° clockwise about the origin.

On a coordinate plane, rectangle P Q R S has points (negative 3, negative 1), (negative 1, negative 1), (negative 1, negative 4), (negative 3, negative 4).

What are the coordinates of R’?
R’(4,–1)
R’(–4,1)
R’(1,4)
R’(–1,–4)

Answer 1

The answer is: R'(-4,1).

Explanation:

If the 90 degree angle is clockwise, the new figure will be in quadrant 2 (or in the section directly above the pre-image). Therefore, (x,y) maps to (y,-x), which will give us (-4,1).

Answer 2

R' (-4 , 1)

Explanation:

Rotation of 90°

(Clockwise)

(x, y) ----> (y, -x) (take opposite of x, then switch the x and y)

Rotation of 90°

(CounterClockwise)

(x, y)------>(-y, x)

Rotation of 180°

(Both Clockwise and Counterclockwise)

(x, y) ----->(-x, -y)

Rotation of 270°

(Clockwise)

(x, y) ----->(-y, x)

Rotation of 270°

(CounterClockwise)

(x, y)------>(y, -x)