Calculate the lengths of the 3 sides of the triangle:
AB =
[tex] \sqrt{(7 - ( - 1)) ^{2} + (( - 2) - ( - 8))^{2} } = 10[/tex]
BC =
[tex] \sqrt{(( - 1) - 5) ^{2} + (( - 8) - 0)^{2} } = 10[/tex]
AC =
[tex] \sqrt{(7 - 5) ^{2} + (( - 2) - 0)^{2} } = 2 \sqrt{2} [/tex]
Because AB = BC
=> ️ABC is an isoscelea triangle at B
