Please help me. I need excel to figure the following formula

Fomula is Q=8.025 CA (h)0.5 where 0.5 is square root.
C=0.61
A=4.91
I will have the value for Q OR H. Which ever one I have I need the answer
for the other.

I now the formula will work when I know Q=41.6 and the answer for h is 3.
I now the formula will work when I know h=10 and the answer for Q is 76.0

Maybe I need two different formulas?
Please Help me I am tired and out of ideas. Thank you soooooo much.