\(YZ =
\sqrt{(-5+4)^{2}}+(-1 - 6)^{2}
\sqrt{1+49}
\sqrt{50}
---
XY=
\sqrt{(-5-7)^{2}}+(-1 - 3)^{2}
\sqrt{144+16}
\sqrt{160}
---
XZ=
\sqrt{(-4-7)^{2}}+(6 - 3)^{2}
\sqrt{121+9}
\sqrt{130}
to get perimeter you add all the sides together
XY + XZ + YZ
\sqrt{130} + \sqrt{50} + \sqrt{160}
= 31.123 (3 d.p.)\)
