Question

3.
1
79° 104°
m∠1 =

Explanation:

Step1: Find the adjacent angle of \(104^{\circ}\)

The adjacent angle of \(104^{\circ}\) is \(180^{\circ}- 104^{\circ}=76^{\circ}\)

Step2: Use the triangle - angle sum theorem

In a triangle, the sum of interior angles is \(180^{\circ}\). Let \(\angle1=x\), then \(x + 79^{\circ}+76^{\circ}=180^{\circ}\)

$$x=180^{\circ}-(79^{\circ}+76^{\circ})$$

$$x = 180^{\circ}-155^{\circ}$$

$$x = 25^{\circ}$$

Answer:

\(25^{\circ}\)