Question

Calcule a distância d entre os pontos A (7,-4) e B (2,8)

Answer 1

$A(7,-4)~~~e~~~~B(2,8) \\ \\ d_{AB}= \sqrt{(x_B-x_A)^2+(y_A-y_B)^2} \\ \\ d_{AB}= \sqrt{(2-7)^2+(8+4)^2 } \\ \\ d_{AB}= \sqrt{(-5)^2+(12)^2} \\ \\ d_{AB}= \sqrt{25+144} \\ \\ d_{AB}= \sqrt{169 } \\ \\ d_{AB}=13$