Proving Congruence
There are multiple ways to prove congruence between two triangles:
- SSS - three sides are congruent
- SAS - two sides and the angle in between are congruent
- ASA - two angles and the side in between are congruent
- AAS - two angles and one side are congruent
- HL - (applies only to right triangles) the hypotenuse and one leg are congruent.
Keep in mind that the order of the letters matters.
Solving the Question
Given triangle JLM, we know that
- S - Z is the midpoint of JM, meaning JZ is congruent to MZ.
- S - Both triangles share side LZ.
- S - Because JLM is an equilateral triangle, LJ is congruent to LM.
This is only one of the ways to prove congruence with these two triangles.