Resolve forces horizontally:

\(P \cos \theta = 12 + 8 \cos 30^\circ - 10 \cos 45^\circ\)

\(P \cos \theta = 11.857\)

Resolve forces vertically:

\(P \sin \theta = 10 \sin 45^\circ - 8 \sin 30^\circ\)

\(P \sin \theta = 3.071\)

Calculate \(P\):

\(P = \sqrt{11.857^2 + 3.071^2}\)

\(P = 12.2\)

Calculate \(\theta\):

\(\theta = \arctan \left( \frac{3.071}{11.857} \right)\)

\(\theta = 14.5\)