Solving an equation system

[ptc-4805829]

I am stuck with 2 different problems.I am using Mathcad 15.

The first one is:

solve the equationsystem

4x-y=12

y+2x=x+1

I need to solve this on Mathcad but I cant seem to figure out how to "combine" the two if you get what I mean.

For the other one. Lets say I have an equation 2x+4=x+y. How do I get Mathcad to solve out y for me?

Thank you very much.

[tdevaraj]

Hi

Problem [1]

You can solve this with solve blocks (either symbolic or numeric examples attached)

Problem [2]

You write the equation and invoke the symbolic solve command from the symbolic tool bar to solve for y.

Hope this helps

[AndyWesterman]

Solution is similar for both questions, but lets consider the 2nd part first:

Enter the equation 2x+4=x+y using the boolean equals ("<ctrl>" "=") - should show in bold typeface.

Add the symbolic evaluation symbol , either from the symbolic toolbar or with "<ctrl>""<shift>" "."( dot)

for the operator placeholder add "solve,y".

the result can be assigned to a new variable.

Note that because I have asked mathcad to assign the result to A it is warning that x is undefined.

This means that it does not have a numerical solution only the symbolic one as shown.

However, if you add a definition for x after the assignment to A and repeat the symbolic evaluation it can give a numeric answer that can be saved & used later.

The first problem is then an extension of this,

create a 2 row X 1 col matrix & enter the equations in the 2 elements of the matrix.

replace the equation ( "2x+4=x+y" above) with the new matrix,

replace the solve,y with a 1 row X 2 col matrix "solve,( x y )"

And it should solve the system.

If you want to use these values later in the work sheet, select all of the text in this region using the <space> key

"<insert>" will swap between the start & end of the region, insert ( a b) := at the beginning to preserve the calculated result.

Regards

Andy