Question

calculate the missing measurement.
∠b = ?°

Explanation:

Step1: Recall the triangle angle - sum theorem

The sum of the interior angles of a triangle is \(180^{\circ}\). So, \(\angle A+\angle B+\angle C = 180^{\circ}\).

Step2: Substitute the known angles

Given \(\angle A = 35^{\circ}\) and \(\angle C=80^{\circ}\). Then \(35^{\circ}+\angle B + 80^{\circ}=180^{\circ}\).

Step3: Solve for \(\angle B\)

First, simplify the left - hand side: \(35 + 80+\angle B=115+\angle B\). Then, \(\angle B=180 - 115\).

Answer:

\(65\)