Question

a = 115
f = ____

Explanation:

Step1: Recall angle - sum property of a triangle

The sum of interior angles of a triangle is 180°.

Step2: Calculate the value of \(f\)

We know that \(f + 57^{\circ}+51^{\circ}=180^{\circ}\). So, \(f=180^{\circ}-(57^{\circ} + 51^{\circ})\).
First, calculate \(57^{\circ}+51^{\circ}=108^{\circ}\). Then, \(f = 180^{\circ}-108^{\circ}=72^{\circ}\).

Answer:

72