Matrix help

[Princevenom]

-1(x1) + 2(x2) - 3(x3) = 8
1(x1) - 7(x2) + 5(x3) = -30
1(x1) - 4(x2) + 4(x3) = -16
6(x1) - 4(x2) + 18(x3) + 1(x4) = -1

can anyone solve this and show me their steps?
thx

 

[stapel]

There are many "right" ways to solve this system of equations. Your subject line mentions one category of ways: using matrices. Are you using row operations? Or inverse matrices? Or your graphing calculator? Or something else?

Please reply showing what you have tried, and we'll be glad to help you find any errors and get moving again toward a solution.

Thank you.

Eliz.

 

[Unco]

-1(x1) + 2(x2) - 3(x3) = 8
1(x1) - 7(x2) + 5(x3) = -30
1(x1) - 4(x2) + 4(x3) = -16
6(x1) - 4(x2) + 18(x3) + 1(x4) = -1

can anyone solve this and show me their steps?

The augmented matrix is:

\(\displaystyle \L\mbox{
\left[
\begin{array}{cccc|c}
6& -4 & 18 & 1 & -1\\
1& -7 & 5 & 0 & -30\\
-1& 2 & -3 & 0 & 8\\
1& -4 & 4 & 0 & -16\\
\end{array}
\right]
}\)

Show your efforts.