This mathematics problem involves applying core mathematical principles and formulas. Below you will find a complete step-by-step solution with detailed explanations for each step, helping you understand not just the answer but the method behind it.
ScanSolve AI Answer
Step 1: Identify the type of triangle. Given that in ABC, BC = AB, this means that ABC is an isosceles triangle. Step 2: Apply the property of isosceles triangles. In an isosceles triangle, the angles opposite the equal sides are equal. Since side BC is opposite A and side AB is opposite C, we have A = C. Step 3: Use the sum of angles in a triangle. The sum of the interior angles in any triangle is 180^. So, A + B + C = 180^. Step 4: Substitute the given values and solve for A. We are given B = 80^. Since A = C, we can substitute A for C in the equation: A + 80^ + A = 180^ 2 A + 80^ = 180^ 2 A = 180^ - 80^ 2 A = 100^ A = (100^)/(2) A = 50^ The final answer is 50^. Drop the next question.