Expert: Richard J. Raridon - 11/22/2009

Question
2q^2-20q=1000/q

What is the process to solve such equations for q?

Answer
The first thing you can do is divide by 2 to get q^2-10q = 500/q
Next, multiply each term by q to get q^3-10q^2 = 500
You can't factor it so re-write it f(q) = q^3-10q^2-500
Put in some value for q and calculate f(q).  If f(q)=0, then q is a solution.  In this case,
f(10) = -500
f(12) = -212
f(13) = 7
So q=13 is close to a solution.  If you want to get closer, try q = 12.99, 12.98, etc.  
There are no solutions for q < 0 so the other two solutions are imaginary.