SOLUTION: A base angle of an isosceles triangle measures 18 degrees. Find the measure of the vertex angle.

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Question 424457: A base angle of an isosceles triangle measures 18 degrees. Find the measure of the vertex angle.
Answer by nerdybill(7384) About Me  (Show Source):
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A base angle of an isosceles triangle measures 18 degrees. Find the measure of the vertex angle.
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Base angles of an isosceles triangle are equal.
And, sum of the three interior angles of a triangle is 180 degrees.
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Let v = vertex angle
then
v + 18 + 18 = 180
v + 36 = 180
v = 144 degrees