Answer:
x = 30°
Explanation:
- the two values are on a straight line, so 180 degrees, we solve with an equation
3x + 1 + 89 = 180
3x = 180 - 1 - 89
3x = 90
x = 90 : 3
x = 30°
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3 x 30 + 1 + 89 = 180
90 + 90 = 180
180 = 180