Rozwiąż układ równań dla x+y=50 i x/2-y/3=0

Rozwiązanie zadanego układu równań metodą podstawiania:

$\begin{cases} x+y=50 \\ \frac{ x}{2}-\frac{y}{3}=0 \end{cases}$

$y+x=50-2y+3x=0 $
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i: Ostateczne rozwiązanie to:

y = -x + 50

  3x - 2•(-x +50) = 0
  5x = 100
  5x = 100 

  x = 20 
  x = 20
  y = -x+50  y = -(20)+50 = 30 
 {x,y} = {20,30}