Question

1. find x.

Explanation:

Step1: Use the triangle - angle sum theorem

The sum of the interior angles of a triangle is \(180^{\circ}\). Let the three angles of the triangle be \(x\), \(25^{\circ}\), and \(115^{\circ}\). Then the equation is \(x + 25^{\circ}+115^{\circ}=180^{\circ}\).

Step2: Solve the equation for \(x\)

First, simplify the left - hand side of the equation: \(x+(25 + 115)^{\circ}=180^{\circ}\), which is \(x + 140^{\circ}=180^{\circ}\).
Then, subtract \(140^{\circ}\) from both sides of the equation: \(x=180^{\circ}-140^{\circ}\).

Answer:

\(x = 40^{\circ}\)