Statements
Reasons
1. ABC is a triangle
1. given
2. y || Z
2. given
3.21 = 25; 2326
13.?
4. m21 = m25; m23 = m26 4. def. =
5.m_1 + m_2 + m23 = m_LAM 5.2 addition postulate
6. mz1 + m2 2 + m23 = 180°6. def. straight angle
7. m25+ m22 + m26 = 180° 7. substitution
Which could be the missing reason in Step 3?
alternate interior angles are congruent
alternate exterior angles are congruent
vertical angles are congruent
corresponding angles are congruent