The midpoint of the line segment AB, where
[tex]A(x_A,\ y_A),\ B(x_B,\ y_B:)\\\\M_{AB}\left(\dfrac{x_A+x_B}{2},\ \dfrac{y_A+y_B}{2}\right)[/tex]
We have
[tex]M_{AB}(10,\ 2)\\A(0,\ -2)[/tex]
Substitute:
[tex]\dfrac{0+x_B}{2}=10\ and\ \dfrac{-2+y_B}{2}=2\ \ \ \ |\cdot2\\\\x_B=20\ and\ -2+y_B=4\ \ \ |+2\\\\\boxed{x_B=20\ and\ y_B=6}[/tex]
Answer: B(20, 6)
