1. Geometry/Trig Name: __________________________
Parallel Lines and Angles Practice – Page 1 Date: ___________________________
Section 1 – Identify each pair of angles. If there is no relationship between the angles, write none. 1 2 9 10 3 4 11 12 5 6 13 14 7 8 15 16
1.) Ð1 and Ð8 _________________________________________________________
2.) Ð13 and Ð8 ________________________________________________________
3.) Ð1 and Ð4 _________________________________________________________
4.) Ð3 and Ð6 _________________________________________________________
5.) Ð6 and Ð ________________________________________________________
6.) Ð5 and Ð ________________________________________________________
7.) Ð5 and Ð9 _________________________________________________________
8.) Ð7 and Ð ________________________________________________________
9.) Ð11 and Ð _______________________________________________________
10.) Ð9 and Ð _______________________________________________________
11.) Ð7 and Ð _______________________________________________________
12.) Ð13 and Ð _______________________________________________________
13.) Ð12 and Ð _______________________________________________________
14.) Ð16 and Ð ______________________________________________________

2. Parallel Lines and Angles Practice – Page 2
Part 2 – Use the diagram below to complete each exercise. All justifications must be written in a formal matter. Example – It would be unacceptable to write “Corresponding Ðs You must instead write, “If lines are parallel, then corresponding angles are congruent.”
1.) Ð7
Justification: _________________________________ __________________________________________________________________________________________________________________________________________
2.) Ð3 and Ð5 are supplementary
Justification: ___________________________________ __________________________________________________________________________________________________________________________________________
a // b 1 2 b 3 4 5 6 a 7 8
3.) Ð5
Justification: ___________________________________________________________ _____________________________________________________________________.
4.) Ð8
5.) mÐ7 + mÐ8 = 180
6.) Ð8
7.) Ð2 and Ð8 are supplementary

3. Parallel Lines and Angles Practice – Page 3
Part 3 – Use the diagram to complete each algebra connection problem. You must show all work. 1.
m1 = x +3 and m5 = 2x – 20.
a // b 1 2
What type of angles are they? _________________________
Congruent or supplementary? __________________________ b 3 4 5 6 a 7 8
x = ________ mÐ1 = _______ mÐ5 = ________
mÐ6 = ___________ mÐ8 = __________ 2.
m3 = 56 and m6 = 2x – 4. 3.
m2 = 3x – 10 and m7 = 2x + 16
What type of angles are they? _________________
Congruent or supplementary? __________________
What type of angles are they? _________________
Congruent or supplementary? __________________
x = ______
mÐ3 = _________ mÐ6 = ________
mÐ5 = _________ mÐ7 = ________
x = ______
mÐ2 = _________ mÐ7 = ________
mÐ1 = _________ mÐ4 = ________ 4.
m4 = 3x – 8 and m6 = x – 4 5.
m1 = 2x – 6 and m7 = x - 3
What type of angles are they? _________________
Congruent or supplementary? __________________
What type of angles are they? _________________
Congruent or supplementary? __________________
x = ______
mÐ4 = _________ mÐ6 = ________
mÐ7 = _________ mÐ8 = ________
x = ______
mÐ1 = _________ mÐ7 = ________
mÐ5 = _________ mÐ6 = ________

4. Geometry/Trig Name: _________________________
Practice: What two lines are parallel (if any) according to the given information? n
REASONS:
A. If corresponding angles are congruent, then lines are parallel.
B. If alternate interior angles are congruent, then lines are parallel.
C. If alternate exterior angles are congruent, then lines are parallel.
D. If same side interior angles are supplementary, then lines are parallel.
E. If same side exterior angles are supplementary, then lines are parallel. l m 17 11 10 12 18 j 9 8 14 6 13 2 1 3 4 5 k 19 7 15 16 20
GIVEN Parallel Lines Reason
Ex. mÐ7 = mÐ8 j // k A
1. mÐ7 = mÐ4 ___________ ___________
2. mÐ5 + mÐ6 = 180° ___________ ___________
3. mÐ8 = mÐ1 ___________ ___________
4. mÐ10 + mÐ7 = 180° ___________ ___________
5. mÐ1 = mÐ ___________ ___________
6. mÐ8 + (mÐ2 + mÐ3) = 180° ___________ ___________
7. mÐ1 = mÐ ___________ ___________
8. mÐ1 + mÐ2 + mÐ3 = 180° ___________ ___________
9. mÐ17 = mÐ ___________ ___________
10. mÐ3 = mÐ ___________ ___________
11. mÐ2 = mÐ ___________ ___________
12. mÐ11 = mÐ ___________ ___________

5. Geometry/Trig Name: _________________________
USING Parallel Line Proofs – Page 1 Date: __________________________
1. Given: g // h and s // t
Prove: Ð15 1 2 9 10 g 3 4 11 12 5 6 13 14 h 7 8 15 16 t s
Statements
Reasons
2. Given: k // m
Prove: Ð1 is supplementary to Ð7 2 6 m 1 5 4 8 k 3 7
Statements
Reasons t

6. C B 3 2 1 A D E USING Parallel Line Proofs – Page 2
3. Given: CD // BE; Ð1
Prove: BE bisects ÐDBA C B 3 2 1 A D E
Statements
Reasons
4. Given: AD // BC; Ð2
Prove: AB bisects ÐCAD C 1 2 A B 3
Statements
Reasons D

7. g h t s PROVING Parallel Line Proofs – Page 3
5. Given: Ð13; t // s
Prove: h // g 1 2 9 10 g 3 4 11 12 5 6 13 14 h 7 8 15 16 t s
Statements
Reasons
6. Given: AB bisects ÐCAD; Ð2
Prove: AD // BC C 1 2 A B 3
Statements
Reasons D

8. PROVING Parallel Line Proofs – Page 4
7. Given: Ð8
Prove: Ð7 2 6 m 1 5 4 8 3 7 k
Statements
Reasons t
8. Given: c // d; Ð1 and Ð14 are supplementary
Prove: a // b 1 2 9 10 a 3 4 11 12 5 6 13 14 b 7 8 15 16
Statements
Reasons c d

9. Parallel Line Proofs – Page 5
9. Given: AB // CD; Ð6
Prove: BC // DE A D B 2 1 3 4 5 7 6 C E
Statements
Reasons
10. Given: BC // DE; Ð6
Prove: AB // CD A D B 2 1 3 4 5 7 6 C E
Statements
Reasons

10. Parallel Line Proofs – Page 6
11. Given: BE bisects ÐDBA; Ð1
Prove: CD // BE C B 3 2 1 A D E
Statements
Reasons
12. Given: Ð2; Ð5
Prove: Ð6
HINT: First prove PQ // RS, then you should just need one more step to get to this prove. P R 3 4 T 2 5 6 S 1
Statements Q
Reasons