I am a new Mathcad user and have a question on solving a simple formula

Hi - I have this question to answer using Mathcad 15 and I'm brand new to using it and just can't get it to work - the question is :

A mechanical control system has a transfer function given by G(w)=8/(6+6wj+(wj)squared)

where w = the angular velocity, I have to find the modulus and argument of the transfer when w = 0.5

I've tried using w:=0.5 and Given and Find but it just doesn't work - can anybody please give a step by step of how to do this please ?

Thanks (in hope !)