Question

a side of the triangle below has been extended to form an exterior angle of 130°. find the value of x. 15° x° 130°

Explanation:

Step1: Recall angle - sum property of a triangle's exterior angle

The exterior angle of a triangle is equal to the sum of the two non - adjacent interior angles.

Step2: Set up the equation

Let the two non - adjacent interior angles be $15^{\circ}$ and $x^{\circ}$, and the exterior angle be $130^{\circ}$. So, $15 + x=130$.

Step3: Solve for $x$

Subtract $15$ from both sides of the equation: $x = 130−15$.
$x = 115$.

Answer:

$115$