Question

30 POINTS!!

Find the measure of angle B in isosceles triangle ABC.

Answer 1

3 angles inside a triangle = 180 degrees

since the 2 sides are equal

angle B and C are the same

180 - 50 = 130 degrees

130 / 2 =65

Angle B is 65 degrees

Answer 2

C. 65 degrees.

Triangles must equal 180 degrees. The given 50 means the rest of the triangle is equal to 130. I believe because of the Side-Angle-Side theorem of triangles (if my knowledge of proofs from 3 years ago is still with me), the two remaining angles are equal to each other. Let's call them X. 2x = 130. Divide both sides by 2. 130/2 = 65. So x=65