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# Mathcad Prime 2.0 - 3 Equations - 3 Unknowns

## Mathcad Prime 2.0 - 3 Equations - 3 Unknowns

(OP)
I am trying to set up a program that solves 3 equations for 3 unknowns to determine my directional stresses in the attached equation. I know r1, r2, and phi, and I am trying to solve for rx, ry, and Txy. Please see attached.

Is there a way in Mathcad Prime 2.0 to set up 3 equations for 3 unknowns and have it solve?

Thank you.

### RE: Mathcad Prime 2.0 - 3 Equations - 3 Unknowns

For a quick answer I would solve numerically using the minerr function as suggested.

If you need a symbolic answer first simplify the equation for phi. Symbolic solvers don't like absolute functions. Solve for the positive case and then the negative case. I will try this problem later on tonight. BTW, I use Mathcad 13 and wxMaxima.

I use Given = Find for symbolic solutions too not just numerical ones.
I solve a lot of system of equations but most are simple polynomials. My gut tells me the symbolic answer is going to be mess.

Peter Nachtwey
Delta Computer Systems
http://www.deltamotion.com

### RE: Mathcad Prime 2.0 - 3 Equations - 3 Unknowns

The problem can be solved symbolically, too, and the result isn't that clumsy ar all.
Don't have a Prime installed here (and if, it would be P3) so here is a screenshot of the solution in Mathcad 15 (still the better version anyway).

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