Answer:
x = 45°
Explanation:
The total measurement is 360° (the measurement of a circle).
Set the equation. Set all measurements equal to 360:
228 + (x + 29) + (x + 13) = 360
Combine like terms:
228 + 29 + 13 + 2x = 360
2x + 270 = 360
Isolate the variable, x. Note the equal sign, what you do to one side, you do to other. Do the opposite of PEMDAS. First, subtract 270 from both sides:
2x + 270 (-270) = 360 (-270)
2x = 360 - 270
2x = 90
Next, divide 2 from both sides of the equation:
(2x)/2 = (90)/2
x = 90/2
x = 45
x = 45° is your answer.
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