The midpoint of the line segment between $(x,y)$ and $(2,4)$ is $(-7,0)$. Find $(x,y)$.

midpoint for x between 2 and -7 would be -2.5

y 4 and 0 would be 2

I can't really understand that, some of it seems blured out

midpoint for y between 4 and 0 would be 2 (-2.5,2)