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# Hi, I really hope you can help me. I have 6 equations...

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 Question by Wlotzkas Submitted on 7/7/2003 Related FAQ: comp.sys.hp48 FAQ : 1 of 4 - Common Questions Rating: Not yet rated Rate this question: N/A Worst Weak OK Good Great Hi, I really hope you can help me. I have 6 equations with 6 unknowns, and would like to solve them using the multiple equation solver of my HP48GX. However, the HP keeps on giving me the message: "Too many unknowns". The Equations are:(1)  A=PI*D^2/4*(2*PI-2*THETA)/2/PI+((D/2)^2-(Y-D/2)^2)^.5*(Y-D/2)(2)   THETA= ACOS((Y-D/2)/(d/2))(3)   P=PI*D*(2*PI-2*THETA)/2/PI(4)   R=A/P(5)   V=-2*(8*9.81*R*S0)^.5*LOG(Ks/14.8/R+0.6275*FI/R/(8*9.81*R*S0)^.5)(6)   Q=V*A Unknowns: A, P, R, Y, THETA, V.  (6 Equations, 6 unknowns) Constants: Q=0.101 m^3/sPI=22/7 DimensionlessD=0.45 mS0=0.002 m/mKs=0.0015 mFI=1.13E-6 m^2/s It is in relation to the flow depth of water in a sewer pipe. If I solve y, the answer should be 0.303m. I saved each equasion in a different name, like A1, P1, etc, and saved { A1 P1 .....} in EQ. Then I pressed MINIT, and then MSOL. All the right vars are there, but I cannot get it to calculate y. However, if I save each equasion under it's var left of the equation mark, (Save V*A in Var Q for example, see equation 6) and solve equation 5 vith the normal equation solver, then I get the right answer. The limitation then is to calculate the other Variables. Does the MSOL function requires a function that needs to be able to be solver without substitution? Can you please direct me to anyone that can help me with this if you can't? I will really appreciate it. Thank you,

 Answer by loser Submitted on 3/17/2004 Rating: Not yet rated Rate this answer: N/A Worst Weak OK Good Great 0123456789 10111213141516171819 20212223242526272829  30313233343536373839 40414243444546474849 50515253545556575859 606162636465676869 70717273747576777879   80818283848586878889 90919293949596979899 100

 Answer by rt Submitted on 5/25/2004 Rating: Not yet rated Rate this answer: N/A Worst Weak OK Good Great 2x+3=6

 Answer by GOD Submitted on 3/12/2007 Rating: Not yet rated Rate this answer: N/A Worst Weak OK Good Great you're ass...

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