Question

What is the midpoint between the points (1, 3) and (5, 7)?

Answer 1

The formula of the midpoint between $A(x_A;\ y_A)$ and $B(x_B;\ y_B)$

$M_{AB}\left(\dfrac{x_A+x_B}{2};\ \dfrac{y_A+y_B}{2}\right)$

We have $A(1;\ 3);\ B(5;\ 7)$

Therefore

$M_{AB}\left(\dfrac{1+5}{2};\ \dfrac{3+7}{2}\right)\to M_{AB}\left(\dfrac{6}{2};\ \dfrac{10}{2}\right)\to M_{AB}(3;\ 5)$

Answer: C. (3; 5)