Question

Which of the following points lies on the graph

Answer 1

Plug in each point. If both sides of the equation are true, then the point is on the graph.

(-3, 21)

y = x^2-2x+6
21 = (-3)^2-2(-3)+6
21=9+6+6
21=21

That works. If you are not 100% confident with your arithmetic, you can plug in the other points.