SOLUTION: find the measure of the vertex angle of an isosceles triangle if the measure of each base angle is 42 degrees

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Question 117646: find the measure of the vertex angle of an isosceles triangle if the measure of each base angle is 42 degrees
Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
The two base angles of a particular isosceles triangle are each 42 degrees. (The base angles
are the angles that are opposite the pair of equal sides of the triangle.) The sum of these
two angles is 42 + 42 = 84 degrees.
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Geometry tells you that the sum of the three angles of a triangle is 180 degrees.
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Then for this problem we know that the sum of two of the three angles is 84 degrees. That
means that the third angle makes up the difference between the 180 degree total and the 84 degrees
of two of the angles.
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So the third angle of this triangle is 180 - 84 = 96 degrees.
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The answer to this problem is that the third angle is 96 degrees.
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Hope this helps you to understand triangles in general and isosceles triangles in particular.
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