WAEC 2023 · Paper 1 · Q12

Given that $M$ is the midpoint of $T(2, 4)$ and $Q(-8, 6)$ , find the length $MQ$ .

Worked solution (try it first)

The midpoint averages the coordinates: $M = \left(\frac{2 + (-8)}{2}, \frac{4 + 6}{2}\right)$
$= (-3, 5)$ .
From $M(-3, 5)$ to $Q(-8, 6)$ the changes are $-5$ across and $1$ up.
By Pythagoras, $MQ = \sqrt{(-5)^2 + 1^2} = \sqrt{26}$ units, option B.