Question

Seja A e B os pontos (1,1) e (5,7) no plano. O ponto médio do segmento AB é

Answer 1

$x_M=\frac{x_A+x_B}{2}=\frac{1+5}{2}=3\\ \\ y_M=\frac{y_A+y_B}{2}=\frac{1+7}{2}=4\\ \\ \boxed{M(3,4)}$

Answer 2

p_m=\left( \dfrac{x_1+x_2}{2},~ \dfrac{y_1+y_2}{2}\right)\\\\\\
p_m=\left( \dfrac{1+5}{2},~ \dfrac{1+7}{2}\right)\\\\\\
p_m=(3,4)~\to~alternativa~A