Sorry, it didn't paste right.
Here is the correct problem:
x + 10y – 2z = 20
5x – 3y + 4z = 8
2x + y = 6
Can you use an inverse matrix to solve
$\displaystyle \left[ {\begin{array}{rrr}1&{10}&{ - 2}\\5&{ - 3}&4\\2&1&0\end{array}} \right]\left[ {\begin{array}{*{20}{c}}x\\y\\z\end{array}} \right] = \left[ {\begin{array}{*{20}{c}}{20}\\8\\6\end{array}} \right]$