Question 998429
Given:  <1 and <2 and congruent;  <1 and <2 are supplementary


Prove:  <1 is a right angle and <2 is a right angle


Statements ----------------                                                                    Reasons

 

1)  
<1 and <2 are congruent     

<1 and <2 are supplementary----------------   given

2)  m<1 = m<2      ----------------  Def of congruent angles

3)  m<1 + m<2 = 180 ----------------  Def of supplementary angles

4)  m<2 + m<2 = 180 ----------------  Substitution

5)  2 (m<2) = 180----------------                                                      Combine like terms or Distributive Property

6)  m<2 = 90 ----------------                                                                Multiplication/Division Property

7)  m<1 = 90 ---------------- Substitution or Transitive Property

8)  <1 is a right <; <2 is a right < ---------------- Def of right angle