An equilateral triangle and an isosceles triangle share a common side. What is the measure of /_ABC?
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The sum of all the angles in a triangle is equal to 180 degrees
For an equilateral triangle, all sides are equal
i.e 60 + 60 + 60= 180
For an isosceles triangle, two sides are equal
the first image is an isosceles triangle why the second image is an equilateral triangle