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Help me pleaseeeeeeeee

Help me pleaseeeeeeeee-example-1
User SammyT
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2 Answers

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In a triangle, the interior angles have a sum of 180 degrees. To determine the value of x, you need to first find the measure of the angle supplementary to the exterior angle.

Since the exterior angle is 129 degrees, the other angle supplementary to it would equal 51.

After you know that, add 51 + 55 = 106

180 - 106 = 74, so the measure of x is 74 degrees.
User Efultz
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Answer:

Angles on a straight line add up to 180 degrees so for the 129 degrees you will take 180 - 129 = 51. In the triangle you will add 51 and 55 = 106 but remember in a triangle all angles should be equal to 180. So 180 - 106 = 74. X=74degrees

User Boris WM
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