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Answer:
m∠A = D. 140°
Let the supplement of angle A be called "Angle B". Assign this angle a value of "x":
Write an equation to represent the value of Angle A: 60 + 2x
Supplementary angles sum up to 180°, therefore:
180 = x + 60 + 2x
Combine like terms and simplify:
180 = 3x + 60
180 - 60 = 3x
120 = 3x
120/3 = 3x/3
x = 40°.
Find the measure of Angle A by substituting this value into the equation:
2(40) + 60 = 140° = m∠A
