Two-colmn Proof - Geometry - Please Help ASAP

Question

This is supposed to be a two column proof. It has statements on one side and reasons on the other.

 

Given:
Triangle ABC with angle C is right angle

Prove:
Angle A and angle B are complementary

 

Thank you in advance!

Answer 1

Given: right triangle ABC, rt. angle at vertex C.

1. angle A + angle B + angle C = 180^o

^{sum of angles, any triangle, is 180 deg.} 

2. angle C = 90^o 

 

 

3. angle A + angle B = 90^o

^{result of subtracting eq. in step 2 from eq. in step 1.}

4. angles A & B are complementary

^{because the sum of their measurements is 90 deg. (cf. step 3).}

Q.E.D.