How do i solve this coordinate grid puzzle?

The sum of two numbers is 86, and their difference is 20. find the two numbers

Complete each statement from the information given and the triangle criterion you used. if the triangles cannot be shown to be congruent, leave the box for the second triangle blank and choose for reason “cannot be determined.” carbon - regular hexagon. ∆can ≅ ∆ by

Factor the polynomial by its greatest common monomial factor.