A postulate is an assumption we use for mathematical reasoning; it isn't yet proven. once it's proven, it becomes a theorem.
The point P has coordinates (x,y) = (-2,6) so x = -2 and y = 6
Replace x and y with those values into the rule given
So,
(x,y) ---> (x-2, y-16)
turns into
(-2,6) ---> (-2-2, 6-16) = (-4,-10)
P = (-2,6)
P ' = (-4,-10)
The answer is -10 because your teacher just wants the y coordinate of point P'
You do 3/5 minus 3/5 which cancels out to 0. Then you do 6 minus 4 which is 2. The answer is 2.
