Question

2x - 5y = -19
x+4y=10
metoda SUBSTITUȚIEi​

Answer 1

Răspuns:

2x-5y=-19|×4 8x-20y=-76

{ =》 {

x+4y=10|×5 5x+20y=50

-13x / =26 =》 x=26:13=》x=2 =》4-10y=-36=》10y=-36-4 =》10y=-40 =》y= -40:10 =》y=-4

S={2,-4}

sper ca te-am ajutat...

atât știu

Answer 2

Răspuns:

2x-5y=-19

x+4y=10  I ×(-2)

________

2x-5y=-19

-2x-8y=-20

_______

 /-13y= -39=>y=39:13=>y=3

x+4×3=10=>x=10-12=>x=-2