As you can notice, the little red square at the bottom means that BAD is a total of 90 degrees.
We can add put equations and find the value of x.
15x - 2 + 7x + 4 = 90
22x + 2 = 90
22x = 88
x = 4
Solve each angle with the value of x.
Angle BAC:
15(4) - 2
60 - 2
58 degrees
Angle CAD:
7(4) + 4
28 + 4
32 degrees
Add to make sure it equals a complementary angle.
58 + 32 = 90 (correct)
Best of Luck!