First, the angles of triangle MNP add up to 180º. Since angle M is 142º and angle P is 24º, angle N must be (180-24-142)º or 14º.
Now angle N is congruent to angle U.
2x - 50 = 14
2x = 64
x = 32
Segment NP is congruent to segment US, so 13 = 2x - y AND x=32.
13 = 62 - y
y = 49