SOLUTION: an isosceles triangle has a vertex angle of 40 degrees.what is the measure of the base angle?

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Question 921727: an isosceles triangle has a vertex angle of 40 degrees.what is the measure of the base angle?
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

an isosceles triangle is a triangle that has two sides of equal length=>
base angles are equal too
if base angle is alpha and a vertex angle of 40 degrees, then
2alpha%2B40=180
2alpha=180-40
2alpha=140
alpha=140%2F2
alpha=70.........the measure of the base angle