Re: Solving multiple equations

*To*: mathgroup at smc.vnet.net*Subject*: [mg125536] Re: Solving multiple equations*From*: Bill Rowe <readnews at sbcglobal.net>*Date*: Sun, 18 Mar 2012 02:40:45 -0500 (EST)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com

On 3/17/12 at 2:52 AM, tmatsoukas at me.com (Themis Matsoukas) wrote: >I have two set of equations, one in the form, >eq1 = ({0.15, 0.85, X1} == {X3, X2 + X4, X5}) >and the other in the form >eq2={1. X1 == 9/5, X4/(X3 + X4 + X5)==1/3} >Solve understands both Solve[eq1] and Solve[eq2] but if I want to >solve the two sets simultaneously, what is the best way to combine >eq1 and eq2 into a single list of equations, either of the form of >eq1 or of eq2, that Solve can understand? In[24]:= NSolve[Join[Thread@eq1, eq2], {X1, X2, X3, X4, X5}] Out[24]= {{X1->1.8,X2->-0.125,X3->0.15,X4->0.975,X5->1.8}} I've used NSolve since the coefficients in the first set of equations are machine precision values.