PQ has endpoints at P (-2,3) and Q (4,1). The center of dilation is (-1,4) and the scale factor is 2. What are the coordinates of the endpoints of P'Q'?

Answer 1

relative to C=(-1,4),
P = (-1,-1)
Q = (5,-3)
So, scaling those coordinates by 2,
P -> (-2,-2)
Q -> (10,-6)
making
P' = (-3,2)
Q' = (9,-2)

That is,
P' = C+2(P-C)
Q' = C+2(Q-C)