Answer:
65 degrees
Explanation:
I recently answered a question in detail that was similar to this one. Feel free to look at my answered questions for it.
For this one, the easiest way to think about it is this. The line on which both angle 4 and angle 1 sit is a straight line, that makes them supplementary angles which is just a fancy word that means if you add them together they equal 180.
(angle 4) + (angle 1) = 180
And if (angle 1) = 115, then that means
(angle 4) = 180 - 115
(angle 4) = 65