answer:
x = 14
explanation:
7x - 1 + 6x - 1 = 180
( group like terms )
7x + 6x - 1 - 1 = 180
( add like terms: 7x + 6x = 13x )
13x - 1 - 1 = 180
( subtract whole numbers: -1 - 1 = -2 )
13x - 2 = 180
( add 2 to both sides )
13x - 2 + 2 = 180 + 2
( simplify )
13x = 182
( divide both sides by 13 )
13x / 13 = 182 / 13
( simplify )
x = 14
