Prove Parallel Lines

Which of the following can not be used to prove l₁//l₂

• ∠1=∠3

• ∠2=∠3

• ∠4+∠5=180⁰

• ∠2+∠4=180⁰

Which of the following can not be used to prove a//b

• ∠3+∠4=180⁰

• ∠1=∠2

• ∠1=∠4

• ∠2+∠4=180⁰

How many of the followings can be used to prove AB//EF: i. ∠B+∠BFE=180⁰; ii. ∠1=∠2; iii. ∠3=∠4; iv. ∠B=∠5

• 1

• 2

• 3

• 4

Which of the following can NOT be used to prove AB//CD?

• ∠B=∠DCE

• ∠D+∠BAD=180⁰

• ∠1=∠4

• ∠2=∠3

Which of the following is not correct?

• If ∠D=∠3, then BE//DF

• If ∠B=∠2, then AB//CD

• If ∠1+∠D=180⁰, then BE//DF

• If ∠1+∠B=180⁰, then AB//CD

Which of the following is correct?

• if ∠1=∠3, then AB//CD;

• if ∠2=∠4, then AD//BC;

• if ∠ADC=∠5, then AD//BC;

• if ∠DAB+∠ABC=180⁰, then AD//BC;

• All the above are correct

Which of the following is correct?

• if ∠1=∠2, then AD//BC;

• if ∠3=∠4, then AB//CD

• if ∠3=∠5, then AB//CD

• if ∠3=∠5, then AD//BC

Find y.

• 50

• 130

Line l and m are cut by transversal n.  Which statement proves that line l is parallel to line m?

• ∠2 ≅ ∠3

• ∠2 ≅ ∠6 

• m∠7 + m∠8 = 180°

• m∠3 + m∠5 = 90°

• No

• Yes, corresponding angles are congruent

• Yes, consecutive interior angles are congruent

• Yes, Alternate interior angles are congruent