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- Thread starter iffah
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Please share your efforts - not in words but mathematical steps.View attachment 29876

I have tried to make X1(s) as a subject from equation 1, F(s) from equation 2, and X3(s) from equation 3. I am stuck as I can't get the picture on how to move these three to get the one equation.

Please show us what you have tried and

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Please share your work/thoughts about this problem.

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That process doesn't sound helpful.View attachment 29876

I have tried to make X1(s) as a subject from equation 1, F(s) from equation 2, and X3(s) from equation 3. I am stuck as I can't get the picture on how to move these three to get the one equation.

You need to eliminate X

It may help you keep track of things if you temporarily define constants so you can write equation 1 as AX

I have tried this method, and this is how I get it. Did you mean that I need to make X2 a subject in the equation that I'm currently trying to solve?That process doesn't sound helpful.

You need to eliminate X_{1}and X_{2}from the three equations. One way would be to solve equation 1 for X_{1}(in terms of X_{2}and X3) and put that into equations 2 and 3. Now you've eliminated X_{1}entirely. Then do similarly with the new equations to eliminate X_{2}as well.

It may help you keep track of things if you temporarily define constants so you can write equation 1 as AX_{1}= BX_{2}+ CX_{3}, and similarly elsewhere.

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If you missed an XView attachment 29879

This is what I have done, when I arrive at the third part there are X1 that I have missed. Do I have to insert the X1 into the equation or do I have to change the Third equation and make the X2 as the subject?

In your final equation you still have all three variables, so there has been no progress, and trying to fix that may make it even worse.