3-phase inductance calculation homework
You should determine the impedance of your load using complex numbers. Once you know the impedance, you can find out the reactive component \$X\$ directly:

$$Z = R + jX$$

The sign of the reactive part of your impedance indicates whether you have an more capacitive (negative reactance) or a more inductive (positive reactance) load. You can then convert from reactance to capacitance or inductance if you know frequency:

$$X_C = (-j)\frac{1}{\omega C}$$
$$X_L = (j)\omega L$$