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solving

solving

(OP)
hi

please can someone help me and tell me what i 'm doing wrong, i haven't used mathCAD in ages and i'm trying to solve like 9 unknowns so i have put them in matrice form but now mathcad is being picky...

i have attached my mcad file,

thanks a lot

tammy

RE: solving

What are the three "1" on the unknowm vector?

RE: solving

You should have 11 rows but you have only 9.

RE: solving

israelkk is right, you have a mismatch of rows in your column vector and your matrix.

However, you can also solve for the unknown column vector using matrix math as below:

Matrix given in the form:  [A]{x}={b}

The solution to {x} is: {x}=([A]^-1)*{b}

Mathcad can perform matrix inversion pretty easily.

Stephen Seymour, PE
Seymour Engineering & Consulting Group
www.seymourecg.com

RE: solving

(OP)
israelkk;
The three 1s on the unknown vector r numbers i actually know  (the big matrice is a set of 9 equations that i'm, tring to solve.)
and yes sorry i made a stupid mistake with the number of zeros so yes it is 11.

seymours 2571;
The matrix A is not square so i can't get the inverse

Is there another way of doing this?
I have tried using transpose but mathcad still wont solve the matrix

Thanks  

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