Answer:
Explanation:
The marked angles have a sum of 90°. This lets you find the unknown angle and the value of x.
42° +3x° = 90°
3x° = 48° . . . . . . . . . subtract 42°. This is the value of the unknown angle
x = 16 . . . . . . divide by 3°
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The value of x is 16.
The measure of the missing angle is 48.