Solutions to these matrices

Hi

This may be basic, but i'd really appreciate some help.

The 3 augmented matrices are in reduced row echelon form. For each state *with a reason* the number of solutions

$\displaystyle \begin{pmatrix}1 &2 & 0 &1 \\0& 0 & 1 & 0 \\0& 0 & 0 & 1\\0& 0 & 0 &0\end{pmatrix}$

$\displaystyle \begin{pmatrix}1 & 2 & 0 &1 \\0 & 0 & 1 &2 \\0& 0 & 0&0\end{pmatrix}$

$\displaystyle \begin{pmatrix}1 & 0 & 0 &1 \\0 & 1& 0 &2 \\0& 0 & 1& 3\end{pmatrix}$

Re: Solutions to these matrices

Quote:

Originally Posted by

**zzizi** Hi

This may be basic, but i'd really appreciate some help.

The 3 augmented matrices are in reduced row echelon form. For each state *with a reason* the number of solutions

$\displaystyle \begin{pmatrix}1 &2 & 0 &1 \\0& 0 & 1 & 0 \\0& 0 & 0 & 1\\0& 0 & 0 &0\end{pmatrix}$

$\displaystyle \begin{pmatrix}1 & 2 & 0 &1 \\0 & 0 & 1 &2 \\0& 0 & 0&0\end{pmatrix}$

$\displaystyle \begin{pmatrix}1 & 0 & 0 &1 \\0 & 1& 0 &2 \\0& 0 & 1& 3\end{pmatrix}$

Try writing each row as an equation with the variables. The answers should then be obvious...

Re: Solutions to these matrices

The soln to this matrix is x1 = 1-2x2

X3=0

But is that enough as explanation?

$\displaystyle \begin{pmatrix}1 &2 & 0 &1 \\0& 0 & 1 & 0 \\0& 0 & 0 & 1\\0& 0 & 0 &0\end{pmatrix}$

Re: Solutions to these matrices

Quote:

Originally Posted by

**zzizi** The soln to this matrix is x1 = 1-2x2

X3=0

But is that enough as explanation?

$\displaystyle \begin{pmatrix}1 &2 & 0 &1 \\0& 0 & 1 & 0 \\0& 0 & 0 & 1\\0& 0 & 0 &0\end{pmatrix}$

Since x_2 is a free variable, wouldn't that mean there are an infinite number of solutions?