Question

could you help me understand how to choose SAS vs ASA when doing triangle proofs? i get them so mixed up.

Answer 1

You're trying to prove that two triangles are similar, or congruent, or whatever. When, for example, you see that one triangle has 2 known angles and one known side inbetween them, and that the other triangle has exactly the same, then you could state that the triangles are congruent by ASA (angle-side-angle).

Or you might note that a side-angle-side combo in one triangle is duplicated in the other triangle. In this case you'd respond with SAS: side, included angle, side.

Answer 2

can you draw what you mean i'm still confused
sorry to keep bugging you

Answer 3

So basically, how I remember SAS is to look for a congruent side. Then look for a congruent angle and another congruent side. In that order. So with that, start with the first pair of congruent sides you see, for example;||, now notice that theres an angle between that side and the "unmarked side". And then there are congruent sides on the other side of the triangle (|)...that might be confusing, but I hoped it help with SAS. Give me a sec and I'll see if I can explain ASA.

Answer 4

OK. So let me just say this first...the easiest way to know which theorem is being used (SAS or ASA) try to see whats on the outside and whats on the inside. Notice how SAS is Side Angle Side, therefore you should have two congruent sides on the outside and a congruent angle on the inside. And that goes for ASA as well, but vice versa. Two congruent angles on the outside and a congruent side on the inside. But heres a picture for ASA.