In this case, we have: `X_L- X_C= 8 - 11 = -3\ Ω`
So `Z = 4 - 3j\ Ω` in rectangular form.
Now to express it in polar form:
Using calculator, we find `r = 5` and ` θ = -36.87^@`.
[NOTE: We usually express the phase angle (when voltage lags the current) using a negative value, rather than the equivalent positive value `323.13^@`.]
So `Z = 5 ∠ -36.87^@\ Ω`