Resposta :
Dab²=(Xb-Xa)²+(Yb-Ya)²
Dab²=(7-1)²+(3-3)²
Dab²=(6)² = 36
Dab=√36 = 6
Dbc²=(Xb-Xa)²+(Yb-Ya)²
Dbc²=(7-7)²+(11-3)²
Dbc²=(8)² =64
Dbc=√64 = 8
Dca²=(Xb-Xa)²+(Yb-Ya)²
Dca²=(1-7)²+(3-11)²
Dca²=(-6)²+(-8)²
Dca²=36+64
Dca²=100
Dca=√100 = 10
Perimetro do Triangulo ABC = 10 + 8 + 6 = 24