## anonymous one year ago GIVING A MEDAL Solve this system of equations using the inverse of a matrix. -x + y = 8 4x + 3y = 12 x − 7y + z = 15 [Hint: AX = B and X = BA-1]

1. anonymous

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2. anonymous

im confused

3. anonymous

do you know how to take the inverse of a function?

4. anonymous

i think it is better to solve by cramer's rule

5. anonymous

@Michele_Laino sorry,but can you solve this also

6. Michele_Laino

here we have to compute the inverse of the subsequent matrix: $\Large \left( {\begin{array}{*{20}{c}} { - 1}&1&0 \\ 4&3&0 \\ 1&{ - 7}&1 \end{array}} \right)$

7. Michele_Laino

which I call with A^-1. After that if I write: $\Large AX = B$ then I can write: $\Large X = {A^{ - 1}}B$