Rotate the point (−1,5)(-1, 5)(−1,5) by 90∘90^\circ90∘ counter-clockwise about the origin.
(1,5)(1, 5)(1,5)
(−5,1)(-5, 1)(−5,1)
(5,1)(5, 1)(5,1)
(−5,−1)(-5, -1)(−5,−1)