The point F( –4,–1) is rotated 270° counterclockwise around the origin. What are the coordinates of the resulting point, F'?

Answer 1

The point F(
–
4,
–
1) is rotated 270° counterclockwise around the origin. What are the coordinates of the resulting point, F'?

Answer 2

If a point (x,y) is rotated 270° counterclockwise, then
newx = xcos270 - ysin270 = x(0) - y(-1) = y
newy = xsin270 + ycos270 = x(-1) + y(0) = -x

so F(-4,-1) ----> F' (-1,4)

check by making a sketch of the result,