Solver could not find a feasible solution, but solutions do actually exist

I have 2 sets of simultaneous equations to solve using solver. When I try to get values of X and Y it says that there is no feasible solution when actual values of X and Y exist. Can someone help me use solver to find the values? I may have done something wrong.

2 Equations:
10^12 = x^2 * Y
2 = (3*Y)/X

I set 2 cells as variable cells (C8 for X, and C9 for Y) and used 2 different cells to type the equations. =C8^2 * C9 and = 3*C9/C8. Then I set objective as the first equation (=C8^2*C9) and set value of 10^12. I then added a constraint which was the second equation (=3*C9/C8) and set that equal to 2. Then I pressed solve and excel says there are no feasible solutions

I suspect that Solver is having trouble with the 1E12 value that is so much larger than the other quantities that it creates instability in the algorithm as set up.

One of the first things I note is that this might be easily solved with solver. A little algebraic manipulation should result in a simple cubic equation that can easily be solved in Excel using the POWER() function (or equivalent).

If you must use Solver, I think you will get a more stable implementation by doing the algebra to find the cubic equation, then find the roots of that cubic equation using solver.

Of course, I am assuming at this point that you will have no trouble with the algebra.

Yes, I have to use solver, I will try to get the cubic equation and do it but I have been told that solver can do it without rearranging the original equation to get the cubic equation.

X= 1.5*Y >>> 10^12 = x^2 * Y so 10^12= 1.5^Y^3 so y= (10/1.5^2)^1/3 etc ...

This is one of those "go to great lengths to avoid algebra" kinds of problems. That's fine because Solver can be used to avoid algebra. Sometimes, we have to be careful in setting up the Solver problem to make sure Solver's algorithms can find a solution.

First step is to look at the different engines and options you are giving to Solver and try different options.

Another thing I would try is to try checking the "show result of each iteration" option and see if you can see a pattern in the values Solver is trying to use.

I don't have immediate access to Excel (and my older version doesn't support all of the same options that you have access to). The challenge here -- especially if we are not going to do any algebra -- is to find the right options for Solver to provide a stable solution to a cubic equation with one very large coefficient and other, smaller coefficients.

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just for the fun, you have to change H1 (starting with 1 and then smaller to end with 1E-6)
With those large numbers is an exact match almost impossible.