How do you find the answer to a algebraic sum of these like terms 7a, 2a, -3a, 5a,

Determine whether angle-angle-angle (aaa) is a valid means for establishing triangle congruence. if it is a valid criterion, explain why. if it is not valid, use geogebra to create a counterexample demonstrating that it doesn’t work and give an explanation. if you construct a counterexample, take a screenshot of your work, save it, and insert the image in the space below.