JAMB Mathematics 2013 Paper

Midpoint of a line PQ where P has coordinates (x${}_1$, y${}_1$) and Q has coordinates (x${}_2$, y${}_2$) is given as

$\left( \frac{x_1 + x_2}{2}, \frac{y_1 + y_2}{2} \right)$.

$\therefore$ If Q has coordinates (r, s), then

$\frac{-2 + r}{2} = 2$ and $\frac{1 + s}{2} = 3$

$-2 + r = 4 \implies r = 6$

$1 + s = 6 \implies s = 5$

Q = (6, 5)