The graph of the equation y = Ax^2 + Bx + C , where are A, B, C integers, is shown below. Find A + B + C.
When x=0, y=0x+0x+7=7, meaning c=7
Likewise, when x=6, y=36a+6b+7=7, meaning 36a+6b=0
When x=3, y=9a+3b+7=1, meaning 9a+3b=−6
So now, we have this system, and we need to solve for a and b:
9a+3b=−6
36a+6b=0