The side given is 110*, and the side underneath that is 90*. If you add it together, That's 200*. Due to the sum property of a quadrilateral, we know that the angles must add up to 360* in total. So, we can simplify it as following.
(2x) + (x+10) = 360-200
2x + (x+10) = 160
2x + x = 160-10
2x + x = 150
x = 50
