Question

rozwiąż ukady równań .;))

a)

2x+5y=2

3(x+y)+2y=3

b)

2x-y=1

3(2x-y)-4(1-x)=3y-1

Answer 1

a)

2x + 5y = 2

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

 

2x + 5y = 2

6x + 3y+ 2y=3

 

2x+5y=2           *(-3)

6x + 5y=3

 

-6x-15y=-6

6x+ 5y=3

+_______________

-10y=-3

y=0,3

 

2x+5y=2

2x=2-1,5

x=0,5

 

b)

2x-y=1

3(2x-y)-4(1-x)=3y-1

 

2x-y=1

6x-3y-4+4x=3y-1

 

2x-y=1             *(-5)

10x-6y=3

 

-10x+5y=-5

10x-6y=3

+_______________

-y=-2

y=2

 

2x-y=1

2x-4=1

2x=5

x=2,5

Answer 2

a)

2x+ 5y = 2

3(x + y) + 2y = 3

 

 

2x+ 5y = 2 /-5y

2x= 2- 5y /:2

x= 1 - 2,5y

 

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

3- 7,5y + 3y + 2y = 3

3- 2,5y= 3 /-3

-2,5y= 0

y=0

 

2x+ 0 = 2 /:2

x=1

 

x=1

y=0

 

b)2x- y = 1

3(2x-y)- 4 (1-x)= 3y - 1

 

2x-y=1 /+y

2x= 1+y /:2

x=0,5 + 1/2y

 

3(2* (0,5+1/2y ) ) - 4(1-0,5 - 1/2y)= 3y- 1

3(1+ y) - 4 - 2 - 2y = 3y- 1

3+ 3y - 6 - 2y = 3y- 1

-3 + y= 3y - 1 /+3

y = 3y +2 /-3y

-2y= 2 / :(-2)

y= -1

 

2x- (-1) = 1

2x+ 1 =1 /-1

2x= 0

x= 0

 

x=0

y= -1