Hi there!
Find m∠GJK by finding the value of its complementary angle and subtracting from 90°.
Using the Alternate Interior Angle theorem:
m∠HJI = m∠JHG, so:
7x - 16 = 5x + 8
Solve for x:
2x - 16 = 8
2x = 24
x = 12
Substitute in this value of x to solve for m∠HJI:
7(12) - 16 = 84 - 16 = 68°
Thus:
m∠GJH = 90 - 68° = 22°