Oh, yes, yes: the polar form is very helpful in this case. So you have

(I am using here as the "polar form" of z, instead of , because it is easier to type.)

Next you can take the fifth root by dividing the exponents on both sides by 5, and you get

Finally subtract 6 and divide by 2: done. - Except that you still need to figure out how manydifferentsolutions you have now got...