Answer:
x = 15
Step-by-step explanation:
If A parallel to B then ∠ 2 and ∠ 4 are same- side interior angles and sum to 180° , then
2x + 10 + 4x + 80 = 180 , that is
6x + 90 = 180 ( subtract 90 from both sides )
6x = 90 ( divide both sides by 6 )
x = 15
