Question

find the value of x.

Explanation:

Step1: Use exterior - angle property

The exterior - angle of a triangle is equal to the sum of the two non - adjacent interior angles.
Let the triangle have interior angles \(a = 58^{\circ}\), \(b\) and exterior angle \(c = 145^{\circ}\).
We know that \(c=a + x\).

Step2: Solve for \(x\)

Rearrange the formula \(145^{\circ}=58^{\circ}+x\) to get \(x = 145^{\circ}-58^{\circ}\).
\(x=87^{\circ}\)

Answer:

\(87\)