How Do You Find Missing Angles in an Isosceles Triangle?

We have a polygon with 3 sides, which means it is a triangle
Since we have 2 congruent sides, we have an isosceles triangle
The angles across from the congruent sides are congruent to each other, so we have two angles that measure x
The three angles of a triangle always add to 180°

1. Our polygon has 3 sides, which means it's a triangle
2. Since two of the sides are the same length, but the third is different, we have an isosceles triangle
1. Isosceles triangles have two equal sides and two equal angles
2. Our triangle has two sides that measure 6
3. The two congruent angles are across from the congruent sides
1. The Triangle Sum Theorem says that the three angles of a triangle always add up to 180°
2. So we can add our three angle measures and set them equal to 180° to solve for x

Find the value of x in the figure below