Answer: x=20 degrees (maybe, and don't consider me smart)
Explanation:
First off, I am a middle schooler and I do RSM so I might've forgotten this stuff because this was in 6th grade RSM so i'll try my best.
So one thing definitely important to note is that line m and n are parallel. So that other line is a transversal, which means there can be some relations with other angles in it.
So straight off 6x+10 is the same as the angle on the other side of the transversal and right near line n (the angle that is not given) which (might) be 130 degrees.
So, then you then know that you form an equation that is 6x+10=130 degrees. If you did algebra, this would be pretty self explanatory, but I will probably have to show it anyways.
6x+10=130 6x=120 x=20 degrees (definitely label it)