Answer:
x = 35°
Step-by-step explanation:
A straight line has an angle of 180 degrees.
Both the 40 degrees's add up to 80, subtract that from 180 and your missing 100.
Meaning (2x + 30)° must equal 100.
2x + 30 = 100 Subtract both sides from 30
2x = 70 Divide both sides from 2 to isolate the variable
x = 35°
