O A. 12x + 20 = 180
O B. 12x = 180
O C. 12x - 20 = 180
D. 8x - 10 = 4x + 10
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Answer:
Answer B. 12x = 180
Step-by-step explanation:
Angles in a Triangle
The sum of the interior angles in a triangle is 180°.
We are given all the angles of the triangle shown in the figure, all of them as a function of x.
Since the sum is 180°:
2x + 4x + 10 + 6x - 10 = 180
Collecting like terms:
12x = 180
This is the equation to find the value of x.
Answer B. 12x = 180