Question

Sistem de ecuații cu metoda reducerii
3x+y=-2
-5x-3y=2
Multumesc

Answer 1

$\left\{\begin{matrix} 3x + y = - 2 \: | \times 3\\ - 5x - 3y = 2\end{matrix}\right.$

$\left\{\begin{matrix} 9x + 3y = - 6\\ - 5x - 3y = 2\end{matrix}\right.$

$9x - 5x + 3y - 3y = - 6 + 2$

$4x = - 4 \: | \div 4$

$x = - 1$

$3x + y = - 2$

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

$- 3 + y = - 2$

$y = - 2 + 3$

$y = 1$

Answer 2

3x+y=-2 |3
-5x-3y=2
urmarim sa reducem termenii in y
9x+3y=-6
-5x-3y=2
4x. / =-4
x=-1

-5x-3y=2
x=-1
5-3y=2
-3y=-3
y=1
verif:
-3+1=-2
5-3=2