you can see it this way, x = -(1/2)y² is just a horizontal parabola opening to the left-hand-side, the -1/2 is just a stretch transformation of the parent function x = y², but as much as it stretches, their vertex is the same, at the origin.
10x=y is the answer your're looking for.
(x+4)(4+x)
(x+4)(x+4) cancel out the 4
answer is C.1<span />
I think the answer is C. 8 ,cause im smart.