Replace x and Y with the points and solve:
4x -2y
(-4,-1) = 4(-4) - 2(-1) = -16 +2 = -14
(-4,-4) = 4(-4) - 2(-4) = -16 +8 = -8
(2,-3) = 4(2) - 2(-3) = 8 + 6 = 14
(3,-5) = 4(3) -2(-5) = 12 +10 = 22
The minimum value ( lowest ) is -14, which would be (-4,-1)