First, you determine the angle measure directly below x. That is a straight line, so it measures 180 degrees. You can add 38 and 90 degrees, and then subtract from 180 to get the last angle measure. This gives you 52. The right 3 angles measure 90 degrees, because they are on the opposite side of a right angle marker. You can add 10 and 52 and then subtract from 90 to get the missing x value, 28.
