#4
1. Ang 1 & Ang 2 are complementary, Ang 2 & Ang 3 are complementary
1. Given
2. mAng1 + mAng2 = 90
mAng2 + mAng3=90
2. Definition of complementary
3. mAng1 + mAng2 = mAng2 + mAng3
3. Substitution
4. Ang 1 = Ang 3
4. Def of congruence
#5
1. Ang1 cong Ang2
1. Given
2. Ang2 cong Ang3
2. Vertical angles
3. Ang1 cong Ang3
3. Transitive property
4. FB bisects Ang AFC
5. Definition of bisect