Geometry

Question Analysis:
This question involves triangle angle sum and isosceles triangle properties.
The main focus is on finding the base angle x when one base angle is given.

Key Concept Explanation:
In an isosceles triangle, the base angles are equal.
The sum of the angles in a triangle is 180°.

Step-by-Step Solution:
Given that AB = AC, triangle ABC is isosceles.
Base angles are equal, so ∠B = ∠C = x = 30°.

Common Mistakes:
Forgetting that base angles are equal in an isosceles triangle.
Confusing the vertex angle with base angles.

Summary:
Base angles in an isosceles triangle a...