PLEASE HELP!! Need help with 3-7

Given: Angles 1 and 2 are a linear pair.
Prove that x = 16

Statements Reasons

1) Angles 1 and 2 are a linear pair. 1) Given
2) Angles 1 and 2 are supplementary. 2) Linear Pair Postulate
3) m∠1 + m∠2 = 180° 3)
4) 10x + 1 + x + 3 = 180 4)
5) 11x + 4 = 180 5)
6) 11x = 176 6)
7) x = 16 7)