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2 votes
Use the matrix method to solve?

-x + 4y = 8
-2x + y = 9
-x = ___a0
-y = ___a1

1 Answer

3 votes
take the coefients and use gausian elimination

\left[\begin{array}{ccc}-1&4&|8\\-2&1&|9\end{array}\right]
multiply top row by -2 and add to 2nd row

\left[\begin{array}{ccc}-1&4&|8\\0&-7&|-7\end{array}\right]
divide bottom row by -7

\left[\begin{array}{ccc}-1&4&|8\\0&1&|1\end{array}\right]
multiply bottom row by -4 and add to top row

\left[\begin{array}{ccc}-1&0&|4\\0&1&|1\end{array}\right]
times top row by -1

\left[\begin{array}{ccc}1&0&|-4\\0&1&|1\end{array}\right]

x=-4
y=1

dunno what the blanks are and the a0 and a1
User Matt Chambers
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