Question

Rezolva sistemul prin metoda substitutiei​

Answer 1

Răspuns:

Explicație pas cu pas:

(x-3y)/6-(y-2)/5=3            [5(x-3y)-6(y-2)]/30=3       5x-21y+12=90

(2x+1)/7-(y-3)/3=3  ⇒        [3(2x+1)-7(y-3)]/21=3  ⇒  6x-7y+24=63  ⇒

5x-21y=78    ⇒ 5x=78+21y  ⇒x= (78+21y)/5

6x-7y=39    ⇒6(78+21y)/5-7y=39  ⇒(468+126y-35y)/5=39  ⇒91y=195-468  ⇒91y=-273  ⇒y=-3  

x= (78+21y)/5 =(78-63)/5  ⇒x=15/5  ⇒x=3