Question

What point is symmetrical to (−1,−3)
for the graph of y=x2+12x+8
?

Answer 1

The axis of symmetry is x = -b/(2a) = -12/2 = -6. Reflecting (-1,-3) across x = -6 gives x' = 2(-6) - (-1) = -11, y' = -3.

So the symmetric point is (-11, -3).