textaufgabe

(1)   2x + 4y = 8

(2)  3*(x - 3) + 4*(y + 1) =17

      3x - 9 +4y +4 = 17

      3x + 4y = 22             (  * (-1) )

(2)  -3x -4y = -22

(1)  2x +4y = 8                               Gleichung (2) und (1) addieren

(2)+(1)      -x = -14      ( * (-1) )   ->    x = 14

in Gl.  (1) eingesetzt     ->     28 + 4y = 8      ->     4y = -20    ->    y = -5

Ergebnis:      x = 14          y = -5

Probe:   $${\mathtt{2}}{\mathtt{\,\times\,}}{\mathtt{14}}{\mathtt{\,\small\textbf+\,}}{\mathtt{4}}{\mathtt{\,\times\,}}\left(-{\mathtt{5}}\right) = {\mathtt{8}}$$      ;  $${\mathtt{3}}{\mathtt{\,\times\,}}\left({\mathtt{14}}{\mathtt{\,-\,}}{\mathtt{3}}\right){\mathtt{\,\small\textbf+\,}}{\mathtt{4}}{\mathtt{\,\times\,}}\left({\mathtt{\,-\,}}{\mathtt{5}}{\mathtt{\,\small\textbf+\,}}{\mathtt{1}}\right) = {\mathtt{17}}$$

Gruß radix !  (Der sich über ein DANKE freuen würde )

Vielen vielen Dank 😊