I looked at the triangle with the angles 50° and 80°. to find the missing angle in that triangle, you want to add the numbers and then subtract 180° from that because when you add all three sides of a triangle, it equals 180°. So when you add 50° and 80°,you get 130°. Now you have to do 180° - 130° and you get 50°. Now that you have the missing angle for the last triangle, you can use that angle to find the measure for the line across from that. To do that, you have to take 180° and subtract 50°. You would get 130°. Your answer for x is 130°.
