Answer:
x = 13
Step-by-step explanation:
6x + 14 + 4x - 8 + 2x + 18 = 180 {Angle sum property of tiangle}
6x + 4x + 2x + 14 - 8 +18 = 180 {Combine like terms}
12x + 24 = 180 {Subtract 18 from both sides}
12x = 180 - 24
12x = 156 {Divide both sides by 12}
x = 156/12
x = 13
