Rozwiąż układ równań dla x-2y+4=0 i x+2y+2=0

Rozwiązanie zadanego układu równań metodą podstawiania:

$\begin{cases}x-2y+4=0 \\ x+2y+2=0 \end{cases}$

$-2y+x=-42y+x=-2 $
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i: Ostateczne rozwiązanie to:

x = -2y - 2

  (-2y-2) - 2y = -4
  - 4y = -2
  4y = 2 

  y = 1/2 
  x = -2y-2
  y = 1/2  x = -2(1/2)-2 = -3 
 {x,y} = {-3,1/2}