Since the 2 angles are complementary they add to 90°, with this information we can form an equation
2(2x-9)+4(x-3)=90
Distribute
4x-18+4x-12=90
Add like terms
8x-30=90
Add 30 to both sides
8x=120
Divide by 8
X=15
Input the solution into the equations for the angle
2(2(15)-9)
2(30-9)
2(21)
42
4(15-3)
4(12)
48