Answer:
A, 80°
Explanation:
This shape has 6 sides.
A 6-sided shape has interior angles that sums up to 720 degrees.
Add the given angles then set it to equal 720 degrees.
Given:
∠134
∠136
∠132
∠78
∠2x
∠x
Add and set it up to equal 720 degrees:
78 + 134 + 136 + 132 + 2x + x = 720
Combine like terms:
(78 + 134 + 136 + 132) + (2x + x) = 720
480 + 3x = 720
Subtract 480 from both sides since the inverse operation of addition is subtraction and we want to get x isolated.
-480 -480
3x = 240
Divide both sides by 3 since the inverse operation of multiplication is division:
/3 /3
x = 80°