Finding the Third Angle of a Triangle

The sum of the interior angles of a triangle are equal to 180o. To find the third angle of a triangle when the other two angles are known subtract the number of degrees in the other two angles from 180o.

Example: How many degrees are in the third angle of a triange whose other two angles are 40o and 65o? Answer: 180o - 40o -65o = 75o


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Find the numbr of degrees in the third angle of each triangle.

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