[latex]A (-2, -2), B (-3, 1), C (7,1) \ \|AB|=sqrt{(x_{2}-x_{1})^2+(y_{2}-y_{1}^2)}\ \|AB|=sqrt{(-3+2)^2+(1+2)^2}=sqrt{(-1)^{2}+3^2}=sqrt{1+9}=sqrt{10}\ \|AC|=sqrt{(7+2)^2+(1+2)^2}=sqrt{9^{2}+3^2}=sqrt{81+9}=sqrt{90}=\ \=sqrt{10*9}=3sqrt{10}\ \|BC|=sqrt{(7+3)^2+(1-1)^2}=sqrt{10^{2}+0^2}=sqrt{100}=10 \ \|AB|^2 + |AC|^2=|BC|^2\ \(sqrt{10})^2+(3sqrt{10})^2=10^2\ \10+9*10=100\ \100=100 \ \L=P[/latex] odp. Jest to trójkąt prostokątny obwód trójkąta : [latex]|AB|=sqrt{10}\ \|AC|=3sqrt{10}\ \|BC|=10 \ \obw =|AB|+|AC|+|BC|\ \obw=sqrt{10}+3sqrt{10}+10=4sqrt{10}+10[/latex] Pole : [latex]P=frac{1}{2}*sqrt{10}*3sqrt{10}=frac{1}{2}*sqrt{100}*3=frac{1}{2}*10*3= 15[/latex]
