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I have several systems of linear equations in matrix form, and I would like to find the $\vec{x}$ that simultaneously solves them: $$A_1\vec{x} = b_1$$ $$\vdots$$ $$A_n\vec{x} = b_n$$ Is there a quick/neat way to do this? That is, something like: $$\text{LinearSolve}[A_1,b_1,\ldots,A_n,b_n]$$ If not, I will take a messy one.

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    $\begingroup$ Stack the matrices and right hand sides and do LinearSolve[Astack,bstack]. Both of these can be done with Join. $\endgroup$
    – Daniel Lichtblau
    Nov 20, 2014 at 23:34
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    $\begingroup$ In other words, use LinearSolve[Join[A1,...,An], Join[b1,...,bn]]. $\endgroup$
    – DumpsterDoofus
    Nov 20, 2014 at 23:36

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Since nobody has posted a "messy" solution yet, let me: if the matrices are in one list alist = {a1,a2,...,an} and the rhs' are in another, blist = {b1,b2,...,bn} then

Clear[x];
vars = x[#] & /@ Range[n];
vars /. Solve[Dot[#1, vars] == #2 & @@@ Transpose[{alist, blist}], vars]
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