Question

escalone e resolva o sistema: (matrizes)
x+5y=3
2x-3y=5

Answer 1

x+5y=3
2x-3y=5
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x=3-5y
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2(3-5y)-3y=5
6-10y-3y=5
-13y=-1
y=1/13
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segunda parte encontra x
x+5*1/3=3
x=9/5

Answer 2

$\left \{ {{x+5y=3} \atop {2x-3y=5}} \right.$

$D= \left[\begin{array}{ccc}1&5\\2&-3\end{array}\right] =-3-10=-13$


$Dx= \left[\begin{array}{ccc}3&5\\5&-3\end{array}\right] =-9-25=-34$


$Dy= \left[\begin{array}{ccc}1&3\\2&5\end{array}\right] =5-6=-1$

$x= \frac{Dx}{D} = \frac{-34}{-13} = \frac{34}{13} \\ \\ y= \frac{Dy}{D} = \frac{-1}{-13} = \frac{1}{13}$

Solução é 
$( \frac{34}{13} , \frac{1}{13} )$