Rozwiąż układ równań dla k+l/2=3 i 2k-1/3l=5

Rozwiązanie zadanego układu równań metodą podstawiania:

$\begin{cases} k+\frac{l}{2}=3 \\  2k-\frac{l}{3}=5 \end{cases}$

$l+2k=6l+6k=15 $
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i: Ostateczne rozwiązanie to:

l = -2k + 6

  6k - (-2k+6) = 15
  8k = 21
  8k = 21 

  k = 21/8 
  k = 21/8
  l = -2k+6  l = -2(21/8)+6 = 3/4 
 {k,l} = {21/8,3/4}