Rozwiąż układ równań dla y=3x-20 i 2x-3y=11

Rozwiązanie zadanego układu równań metodą podstawiania:

$\begin{cases}y=3x-20 \\ 2x-3y=11 \end{cases}$

$-3x+y=-202x-3y=11 $
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i: Ostateczne rozwiązanie to:

y = 3x - 20

  -3•(3x-20) + 2x = 11
  - 7x = -49
  7x = 49 

  x = 7 
  y = 3x-20
  x = 7  y = 3(7)-20 = 1 
 {y,x} = {1,7}