19. Given:
Prove:m∠3 = 70º

Given
m∠2 = m∠4 Definition of congruent angles
m∠4 = 110º b. ________
∠3 and ∠4 are a linear pair Definition of a linear pair (shown in diagram)
∠3 and ∠4 are supplementary Linear Pair postulate
m∠3 + m∠4 = 180º c. _______
m∠3 = 70º d. ________

20. Write a two-column proof.

Given: 7y = 8x – 14; y = 6

Prove: x = 7

Question

19. Given:
Prove:m∠3 = 70º

                        Given
m∠2 = m∠4                                    Definition of congruent angles 
m∠4 = 110º                                    b. ________
∠3 and ∠4 are a linear pair               Definition of a linear pair (shown in diagram)            
∠3 and ∠4 are supplementary           Linear Pair postulate
m∠3 + m∠4 = 180º                         c. _______
m∠3 = 70º                                       d. ________

20. Write a two-column proof.

Given: 7y = 8x – 14; y = 6

Prove: x = 7