Answer:
The correct answer is option B. 140
Explanation:
From the figure we can see that,
AB ║ CD
To find the value of x
From the figure we can see that,
<CFE = <BEF [Alternate interior angles are equal]
4x + 20 = 5x - 10
5x - 4x = 20 + 10
x = 30
To find the measure of <BEF
m<BEF = 5x - 10
= (5*30) - 10
= 150 - 10
= 140°
Therefore the correct answer is option B. 140