Question

to tylko jeden punkt plisss o szybkie rozwiazanie rozwiaz rownanie albo metoda podstawiania albo metoda dodawania stronami.

1/3(x-y+ 3) = 4+y

y-2= 3/4(x-y-2)

Answer 1

1/3(x-y+ 3) = 4+y     /·3

y-2= 3/4(x-y-2)       /·4

 

 

{x-y+3=12+3y

{4y-8=3x-3y-6 

 

{x-y-3y=12-3

{4y-3x+3y =-6+8

 

{x-4y=9

{7y-3x =2

 

{x=9+4y

{7y-3(9+4y)=2

 

{x=9+4y

{7y-27-12y=2

 

{x=9+4y

{-5y=2+27

 

{-5y=29  /:(-5)

{x=9+4y

 

{y=-29/5=-5,8

{x=9+4·(-5,8)=9+(-23,2)=-14,2

 

 

 

 

 

 

Answer 2

(1/3) ( x - y + 3) = 4 + y  / * 3

y - 2 = ( 3/4)(x - y - 2)    / * 4

-----------------------------

x - y + 3 = 12 + 3 y

4 y - 8 = 3 x - 3 y - 6

---------------------------

x - 4 y = 9   / * 3

- 3 x + 7 y = 2

-----------------------

3 x - 12 y = 27

- 3 x + 7 y = 2

------------------   dodajemy stronami

- 5 y = 29

y = - 29/5

x = 9 + 4 y = 9 + 4*( -29/5)

x = 9 - 116/5 = 45/5 - 116/5 = - 71/5

Odp. x = - 71/5,   y = - 29/5

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