I'm solving a fairly simple circuit with dual power supplies and it's just not working nor can I see my way to do it in LTSpice. Here is what I have.

Sorry, it seems all my finely crafted subscripts disappeared in the cut and paste process.

V1 = I1*6420Ω + I2*820Ω = 10

V2 = I1*820Ω + I2*3220Ω = 10

Solving for dual linear equations I get

I1 = 1.2mA I2 = 2.8mA and I3 = I1 + I2 = 3mA which is wrong

therefore voltage drops across resistors are

VR1 = I1*5600Ω = 6.72V which is wrong

VR2 = I2*2400Ω = 6.72V also wrong

VR3 = I3*820Ω = 9.18V again wrong

VR1 + VR3 nor VR2 + VR3 = 10V so the problem must be in the original linear equations for the circuit...

Putting it into LTSpice also not working for me...

V1 = I1(R1 + R3) + I2(R3) = I1*6420Ω + I2*820Ω = 10V I don't see a problem here or in

V2 = I1*820Ω + I2*3220Ω = 10

Solving dual linear equations is like doing long division with numbers to 10 decimal places by hand so I use this:

www.webmath.com/solver2.html

Which I have often used and has proved to be correct in the past. I do not see what I am doing wrong here??? I can only conclude that the initial equations must be incorrect but I can't find the error.

Also in the original CKT diagram there is no ground and the V floats, but LTSpice has to have a gnd reference to analyze. Still not quite up to speed with LTspice.

Sorry, it seems all my finely crafted subscripts disappeared in the cut and paste process.

V1 = I1*6420Ω + I2*820Ω = 10

V2 = I1*820Ω + I2*3220Ω = 10

Solving for dual linear equations I get

I1 = 1.2mA I2 = 2.8mA and I3 = I1 + I2 = 3mA which is wrong

therefore voltage drops across resistors are

VR1 = I1*5600Ω = 6.72V which is wrong

VR2 = I2*2400Ω = 6.72V also wrong

VR3 = I3*820Ω = 9.18V again wrong

VR1 + VR3 nor VR2 + VR3 = 10V so the problem must be in the original linear equations for the circuit...

Putting it into LTSpice also not working for me...

V1 = I1(R1 + R3) + I2(R3) = I1*6420Ω + I2*820Ω = 10V I don't see a problem here or in

V2 = I1*820Ω + I2*3220Ω = 10

Solving dual linear equations is like doing long division with numbers to 10 decimal places by hand so I use this:

www.webmath.com/solver2.html

Which I have often used and has proved to be correct in the past. I do not see what I am doing wrong here??? I can only conclude that the initial equations must be incorrect but I can't find the error.

Also in the original CKT diagram there is no ground and the V floats, but LTSpice has to have a gnd reference to analyze. Still not quite up to speed with LTspice.

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