Here,
The two lines l and m are parallel,
cut by a transversat line t
So The two angles are supplementary each other.
we know that,
The sum of two supplementary angles are 180°
According to the question,
(17x+14)°+(4x-2)°=180°
17x+14°+4x-2°=180°
17x+4x+14°-2°=180°
21x+12°=180°
21x=180°-12°
21x=168°
x=168°/21
x=8°
Therefore,
The value of x is 8°