Question

Rezolvati sistemul -2x+3y=11
7x+y=-4

Answer 1

Răspuns:

x = -1  ; y = 3

Explicație pas cu pas:

-2x +3y = 11

7x +y = -4    => y = -4-7x  (substitutie)

-2x +3·(-4-7x) = 11  <=>

-2x-12-21x = 11

-23x = 23 => x = 23:(-23) => x = -1

y = -4-7·(-1) = -4+7 =3  => y = 3

Answer 2

Răspuns:

-2x+3y =11 -2x+3y=11 -2x+3×(-4-7x)=11 -2x-12-21x

7x+y =-4 y=-4-7x y=-4-7x y=-4-7x

-23x-12=11 -23x= 23 x=-23/23 x=-1

y= -4 -7×(-1) y=-4+7 y=3