SOLUTION: Given:<1 and <2 are supplementary <2 and <3 are congruent Prove: m<1+m<3=180 I need the statements and reasons and the reason have to be a poroperty.

Algebra ->  Geometry-proofs -> SOLUTION: Given:<1 and <2 are supplementary <2 and <3 are congruent Prove: m<1+m<3=180 I need the statements and reasons and the reason have to be a poroperty.       Log On


   

Question 907668: Given:<1 and <2 are supplementary
<2 and <3 are congruent
Prove: m<1+m<3=180
I need the statements and reasons and the reason have to be a poroperty.
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Basic Idea


<1 and <2 are supplementary ... given
<2 and <3 are congruent ... given


<1 + <2 = 180 ... angles 1 and 2 are supplementary
<2 = <3 ... since <2 and <3 are congruent

Since <1 + <2 = 180 and <2 = <3, we can replace the "<2" with "<3" to get <1 + <3 = 180. We are using the substitution property.

This isn't the formal proof, but it gives you an idea of how to do it.