Question

a side of the triangle below has been extended to form an exterior angle of 141°. find the value of x.

Explanation:

Step1: Find adjacent interior angle

The exterior angle and $x^\circ$ are supplementary, so:
$x + 141 = 180$
$x = 180 - 141$
$x = 39$
(Note: The right angle confirms this is a right triangle, but we only need the supplementary angle property here to solve for $x$.)

Answer:

$39$