Answer:
B. 140
Explanation:
With this chart, you must know the fundamentals of the angles. In this case, angle c and e are supposed to equal to 180. In the question, it gives us both the formulas for both angles. So adding them up to 180 will give us x
(x - 10) + (2x + 40)
with a trusty calculator, you will get
= 3x + 30
Now equal this equation to 180
3x + 30 = 180
3x = 180 - 30
3x = 150
Now divide 150 to 3
150 divided by 3 = 50
x = 50
Now just add the x to the angle c
2(50) + 40
=140
To further check if its correct, add the x to angle e
(50) - 10
=40
140 +40 = 180
So the answer would be 140