Question

find ( mangle3 ).

Explanation:

Step1: Use the triangle angle - sum property

In a right - triangle (the one with angle \(51^{\circ}\) and \(\angle3\)), the sum of angles is \(90^{\circ}\).

Step2: Calculate \(\angle3\)

We know that \(\angle3=90^{\circ}-51^{\circ}\)

Answer:

\(39^{\circ}\)