Jawaban: y' = -x'² + 14x'
Penjelasan:
Misalkan titik asalnya (x,y)
Ref y=1
(x,y) ---> (x,2(1)-y)=(x,2-y)
dilanjutkan, ref x=2
(x,2-y) ---> (2(2)-x, 2-y) = (4-x, 2-y)
jadi
x' = 4-x maka x = 4-x'
y' = 2-y maka y = 2-y'
Persamaan bayangannya
y = x² - 2x - 8
2-y' = (4-x')²-2(4-x')-8
-y' = x'² - 16x' + 16 - 8 + 2x' - 8
y' = -x'² + 14x'