from what I remember from what my teacher taught me was that its nonlinear. I'm 98% sure its nonlinear
I'm am so sorry if I get it wrong. I'm apologizing ahead. if you want you can get the points back I dont mind because I feel bad when I get things wrong but I'm pretty sure its non linear
Congruence method: AAA, ASA, SSS,SAS,HL(For right triangle).
For coordinates proof, if you are proficient with vector, then it will be easier to calculate the angles, otherwise, you should know the distance formula and calculate the length of the vertices.
