Given: In Triangle XYZ, mZY= 50°, and 2X = ZZ Prove: mZZ = 65°
А
=
B
Statement:
Reason:
1.XYZ is a triangle
1. Given
2. m2X+mZY+mZZ = 180° 2. Postulate
3. mZY = 50°
3. Given
4. ZX=ZZ
4. Given
5.mZX = mZZ
5. Congruency
6. mZZ + 50° + mZZ = 180° 6.[ ? ]
7.mZZ+mZZ = 130° 7.
8.2(m ZZ) = 130° 8. Algebra
9.mZZ = 65°
9. Division Property
of Equality
D