Question

Dados os pontos P(-1, 4) ; Q(2, 2) e R(-2, -1), qual o perímetro do triângulo PQR ??

Answer 1

$d(P,Q)=\sqrt{(x_p-x_q)^2+(y_p-y_q)^2}\\{d}(P,Q)=\sqrt{(-1-2)^2+(4-2)^2}\\d(P,Q)=\sqrt{13}\\\\d(P,R)=\sqrt{(x_p-x_r)^2+(y_p-y_r)^2}\\d(P,R)=\sqrt{(-1-(-2))^2+(4-(-1))^2}\\d(P,R)=\sqrt{26}\\\\d(Q,R)=\sqrt{(x_q-x_r)^2+(y_q-y_r)^2}\\d(Q,R)=\sqrt{(2-(-2))^2+(2-(-1))^2}\\d(Q,R)=5\\\\\boxed{Per\'imetro=\sqrt{13}+\sqrt{16}+5}$