Could you help me with making x the subject of this equation please?

v^2 = w^2(a^2-x^2)

The answer in my text book is x = ((w^2 a^2 - v^2)^(1/2))/w

Sorry that may not make sense, I wasn't sure how to write it...

I've tried things like...

(v^2/w^2) = a^2 - x^2

(v^2/w^2) - a^2 = x^2

But never seem to get the right answer.

Thanks.