Question

2.) x = __________

Explanation:

Step1: Identify angle - relationship

Assume the two angles are corresponding angles or alternate - interior angles (if lines m and n are parallel), so they are equal.
$2x + 15=135$

Step2: Solve for x

Subtract 15 from both sides: $2x=135 - 15$.
$2x = 120$
Divide both sides by 2: $x=\frac{120}{2}$

Answer:

$x = 60$