What are the angle measures?
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a. Equation:
3x + 21 = 6x - 60 {measure of corresponding angles is the same}
3x - 6x = -60 - 21
- 3x = - 81
b. Value of x:
x = 27
c. Ange measures:
3x + 21 = 3×27 + 21 = 81 + 21 = 102°
or:
6x - 60 = 6×27 - 60 = 162 - 60 = 102°