Question

The vertices of / are g(–4, 0), h(5, 2), and i(–2, –3). / is rotated 270° counterclockwise about the origin to form /. what are the coordinates of the vertices of /?

Answer 1

Use 
r[270]=r[-90] : (x,y) -> (y,-x)

g(-4,0) -> g'(0,4)
h(5,2) -> h'(2,-5)
i(-2,-3) -> i'(-3,2)