Solve a quadratic with trigonometric values in degrees

[axekick]

I'm about to give up on this calculator. I've used it for quite a few classes but usually my problems had numbers that worked out better and this calculator is not going to work for me on exam day if it won't solve these seemingly simple equations. I'm on a new problem now, again I know what the answer is from the solution manual but I can't get to it with my calculator and I've spent hours trying to figure out how. We're not even to the hard stuff yet and I'm scared! The algebra problem I'm stuck on is:

d*cos(30) = 25*sqrt(d/9.81)

The solution is d=84.95. I can't even get my calculator to give me a solution. I've tried solve, solvevx (using x as my variable), zeros and the equation solver with no luck.