$\"\"$

Given that $\"\"$ .

Since $\"\"$ are alternate exterior angles.

Since the line l parallel to m so their alternate exterior angles must be congruent.

So, $\"\"$

$\"\"$ (Definition of congruent angles)

$\"\"$ (Add 4 to each side)

$\"\"$ (Divide each side by 9)

$\"\"$ (Divide: $\"\"$ ) $\"\"$

The value of x is 16.