Question

an equilateral triangle and an isosceles triangle share a common side. what is the measure of angle ABC?the measure of angle ABC is......°(simplify your answer)

Answer 1

Answer: 50 degrees

From the figure, triangle ABD is an Isosceles triangle while triangle BCD is an equilateral triangle

The sum of all the all angles in a triangle is 180 degrees

Also, in an Isosceles triangle, the base angles are equal

65 + < ABC + 65 = 180

< ABC + 130 = 180