Solving equations in excel or other solvers

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likephysics
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Need to find optimal solution by solving 2 equations

X= VR*(R2+R1)/R2 - VN*R1/R2
Y= VR*(R2+R1)/R2 - VP*R1/R2

VP, VN are fixed. VP=5 & VN=0
VR can change. R1,R2 should be same.
How do I find a combo of VR, R1, R2 so that -

X = 0.46 & Y = 0.214 (this part is easy)

The same values of R1, R2 (but VR may be different) should yield -
X = 1.14 & Y = 0.36

I want the X & Y values to be close(15%) to these, not necessarily exact.

How do I do it in excel or some other free math tools?
 
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likephysics said:
Need to find optimal solution by solving 2 equations

X= VR*(R2+R1)/R2 - VN*R1/R2
Y= VR*(R2+R1)/R2 - VP*R1/R2

VP, VN are fixed. VP=5 & VN=0
VR can change. R1,R2 should be same.
How do I find a combo of VR, R1, R2 so that -

X = 0.46 & Y = 0.214 (this part is easy)

The same values of R1, R2 (but VR may be different) should yield -
X = 1.14 & Y = 0.36

I want the X & Y values to be close(15%) to these, not necessarily exact.

How do I do it in excel or some other free math tools?

How would you do it in a paid tool? The point is, you need to formulate the answer MATHEMATICALLY. Translating that into a tool, free or paid, is usually trivial.

"If you can't do it without a computer then WITH a computer it will just take you more time to not be able to do it"
 
likephysics, do you have the Solver plug-in for Excel? In general, that would be useful for problems like this. However, this problem appears unsolveable:

If R1 and R2 are the same, then (since R1=R2) your equations become

X= VR*2 - VN*1
Y= VR*2 - VP*1​

Moreover, if VN=0 and VP=5,

X = VR*2
Y= VR*2 - 5 = X - 5​

So only solutions where Y=X-5 are possible.