Hey there! I'm happy to help!
Angles A and B are alternate exterior angles: they are on the outside of the parallel lines and opposite sides of the transversal. This means that they are congruent. So, we can set up an equation.
6x-2=4x+48
We subtract 4x from both sides.
2x-2=48
We add 2 to both sides.
2x=50
Divide both sides by 2.
x=25.
Have a wonderful day! :D