Question

Układ równań...Proszę o pilne rozwiązanie!!! Daje naj za dobrą odpowiedź.. 3(x+y)-2(x-y)= -1

x-2(x+y)= 3

Answer 1

 3(x+y)-2(x-y)= -1

x-2(x+y)= 3

 

 

3x + 3y - 2x + 2y = -1

x - 2x - 2y = 3

 

 

x + 5y = -1

-x - 2y = 3

 

 

x = -1 - 5y

-(-1-5y) - 2y = 3

 

 

x = -1 -5y

1 + 5y - 2y = 3

 

 

 

 x = -1 -5y

3y = 2     /:3

 

 

x = -1-5y

y = 2/3

 

 

 x = -1 -5*2/3    = -1 - 10/3  = -3/3 - 10/3 = -13/3

y = 2/3

 

 

x =-13/3

y = 2/3

Spr.

L =  x + 5y =  -13/3 + 5*2/3 = -13/3 + 10/3 = -3/3 = -1

P = -1

 

 

 

 

Answer 2

3(x+y)-2(x-y)= -1

x-2(x+y)= 3

 

3x+3y-2x+2y=-1

x-2x-2y=3

 

x+5y=-1

-x-2y=3

 

3y=2

y=2/3

 

x=-1-5y

x=-1-5*2/3

x=-1-3i1/3

x=-4i1/3

 

x=-4i1/3

y=2/3