Question

Rezolvati prin metoda reducerii pentru rezolvarea sistemelor de ecuatii :
1) 3x+2y-1=0
2x+3y-4=0
2)3x+2y=1
2x+3y=4.
Va rog !!!

Answer 1

$1)\left\{\begin{matrix} 3x + 2y - 1 = 0\\ 2x + 3y - 4 = 0\end{matrix}\right.$

$\left\{\begin{matrix} 3x + 2y = 1 \: | \times 3\\ 2x + 3y = 4 \: | \times ( - 2)\end{matrix}\right.$

$\left\{\begin{matrix} 9x + 6y = 3\\ - 4x - 6y = - 8\end{matrix}\right.$

$9x - 4x + 6y - 6y = 3 - 8$

$5x = - 5 \: | \div 5$

$x = - 1$

$3x + 2y = 1$

$3 \times ( - 1) + 2y = 1$

$- 3 + 2y = 1$

$2y = 1 + 3$

$2y = 4 \: | \div 2$

$y = 2$

Answer 2

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