Warm Up

2.7 Transitive and Substitution Property

Remember train of logic: <B <A < A <C <B <C If <B is to <A and <A is to <C then <B is to <C

Substitution Property

Example: <1 comp <2 given <2 <3 given <1 comp <3 If an angle is a comp. to angles, then it is a complement to both angles. (substitution)

Write a proof

Remember, you can substitute <3 in for <1 so that <3 + <2 = 90.

Once you find that y = x, you can substitute x in for y for either angle since they are both congruent to <Q.