Looking at the diagram, you can see that the 130 degree angle and the angle next to it are supplementary angles, meaning that since they make up a line, together they’re 180 degrees. This means that the angle inside the triangle that isn’t y degrees is 180-130, or 50 degrees.
From there, a triangle has 180 degrees. Using that knowledge, you can find the sum of both of the y angles by subtracting the 3rd angle from the 180 total degrees. 180-50=130. That means that 2y=130. You divide both sides by 2, to get y=65, meaning the answer is C.
Hope that helps!
