Question

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

Explanation:

Step1: Recall exterior - angle property

The exterior angle of a triangle is equal to the sum of the two non - adjacent interior angles. So, $130=x + 115$.

Step2: Solve for $x$

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

Answer:

$x = 15$