Question

find m∠bec. m∠bec = ?

Explanation:

Step1: Recall the sum of angles in a right - angle and a straight - angle

We know that \(\angle AEB = 90^{\circ}\) (right - angle) and \(\angle AED=180^{\circ}\) (straight - angle). Also, \(\angle AED=\angle AEB+\angle BEC + 48^{\circ}\).

Step2: Substitute the known values into the angle - sum formula

Since \(\angle AED = 180^{\circ}\) and \(\angle AEB = 90^{\circ}\), we substitute into the equation \(180^{\circ}=90^{\circ}+\angle BEC + 48^{\circ}\).

Step3: Solve for \(\angle BEC\)

First, simplify the right - hand side of the equation: \(90^{\circ}+48^{\circ}+\angle BEC=138^{\circ}+\angle BEC\). Then, using the equation \(180^{\circ}=138^{\circ}+\angle BEC\), we subtract \(138^{\circ}\) from both sides. So, \(\angle BEC=180^{\circ}-138^{\circ}\).

Answer:

\(42\)