Question

{3x-2(y+4)=8
{4(x+1)+5y=10

Repede dau coroana si inima va rog!!!!!

Answer 1

Răspuns:

{x = 4

{y = -2

Explicație pas cu pas:

{3x - 2(y + 4) = 8 {x = 16/3 + 2/3y

{4(x + 1) + 5y = 10 {4(x + 1) + 5y = 10

4 × (16/3 + 2/3y + 1) + 5y = 10

4 × (19/3 + 2/3y) + 5y = 10

76/3 + 8/3y + 5y = 10

76/3 + 23/3y = 10

76 + 23y = 30

23y = 30 - 76

23y = -46

y = -46 : 23 = -2

x = 16/3 + 2/3y = 16/3 + 2/3 × (-2)

x = 16/3 - 2/3 × 2

x = 16/3 - 4/3

x = 4

{x = 4

{y = -2

Answer 2

{3x-2(y+4)=8

{4(x+1)+5y=10

=> {x=16/3+2/3y

{4(x+1)+5y=10

4•(16/3+2/3•y+1)+5y=10

76/3+8/3y+5y=10

76/3+(8+15)/3•y=10

76/3+23/3•y=10

76+23y=30

23y=30-76=-46

y=-46:23=-2

x=16/3+2/3y=16/3+2/3•(-2)=4

(x,y)={(4;-2)}