# Remove redundant equation to solve the needed variables?

Posted 11 days ago
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 Hi,I have revised the equations and fixed the errors. I need to solve the needed variables. I think there are redundant equations since I am looking for seven variables and there are nine equations. I don't guess which ones to be removed? The ones that are not to be removed for sure are:PPA0 + PPA1 + PPA2 + PPA3 == 1 and PPB0 + PPB1 + PPB2 == 1 Please find the file attached. Appreciate your kind help. Attachments:
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Posted 11 days ago
 Your equations seem to be inconsistent: Eliminate[{D11 PPA0 == (1 - d1) P11 PPA1, (D22 + (1 - d1) P11) PPA1 == D11 PPA0 + (1 - d2) P22 PPA2, (2 (1 - d2) P22 + D33) PPA2 == D22 PPA1 + D22 PPB1 + (1 - d3) P33 PPA3, (1 - d3) P33 PPA3 == D33 PPA2, PPA0 + PPA1 + PPA2 + PPA3 == 1, D11 PPB0 == (1 - d1) P11 PPB1, (2 D22 + (1 - d1) P11) PPB1 == D11 PPB0 + (1 - d2) P22 PPA2 + (1 - d2) P22 PPB2, D22 PPB1 == (1 - d2) P22 PPB2, PPB0 + PPB1 + PPB2 == 1}, {PPA0, PPA1, PPA2, PPA3, PPB0, PPB1, PPB2}] D11^2 (-1 + d2) D22^2 D33 P22 == 0
Posted 11 days ago
 When I run Eliminate it returns: D11 (-1 + d2) D22 D33 P22 == 0 ?? Actually d2 cannot be zero. Is there other approximation technique to estimate the variables ?
Posted 11 days ago
 If I used only PPA0 + PPA1 + PPA2 + PPA3 ==1 I got the following: {{PPA0 -> 0.367931, PPA1 -> 0.272443, PPA2 -> 0.203368, PPA3 -> 0.156258, PPB0 -> 0.367931, PPB1 -> 0.272443, PPB2 -> 0.203368}} If I used only PPB0 + PPB1 + PPB2 == 1 I got the follwing: {{PPA0 -> 0.436071, PPA1 -> 0.322898, PPA2 -> 0.241031, PPA3 -> 0.185196, PPB0 -> 0.436071, PPB1 -> 0.322898, PPB2 -> 0.241031}} But I need both conditions !
Posted 10 days ago
 When I used PPA0 + PPA1 + PPA2 + PPA3 + PPB0 + PPB1 + PPB2 == 1 I got the following: {{PPA0 -> 0.199557, PPA1 -> 0.147766, PPA2 -> 0.110302, PPA3 -> 0.0847503, PPB0 -> 0.199557, PPB1 -> 0.147766, PPB2 -> 0.110302}}
Posted 11 days ago
 The equations are inconsistent so redundancy is more or less meaningless in this setting. Do you want a least-squares solution? Saying that two equations need to be removed gives no useful guidance as to which two should go.