Question

Calcule (1/3y^2-4/7y^3) * (-3y)

Answer 1

Resposta:

2x+y/3=10-y+2

3y/2+5x=4x+y-6

{ 2x + y/3 = 10 - y + 2

2x + y/3 = 10 + 2 - y

2x + y/3 = 12 - y

2x + y/3 + y = 12

y

2x + ---- + y = 12 mmc = 3

3

3(2x) + 1(y) + 3(y) = 3(12)

--------------------------------- FRAÇÃO com igualdade despreza o denominador

3

3(2x) + 1(y) + 3(y) = 3(12)

6x + 1y + 3y = 36

6x + 4y = 36

3y/2+5x=4x+y-6

3y

----- + 5x = 4x + y - 6 mmc = 2

2

1(3y) + 2(5x) = 2(4x) + 2(y) - 2(6)

----------------------------------------- FRAÇÃO com igualdade despreza o

2 denominador

1(3y) + 2(5x) = 2(4x) + 2(y) - 2(6)

3y + 10x = 8x + 2y - 12

3y + 10x - 8x - 2y = - 12

3y - 2y + 10x - 8x = -12

1y + 2x = -12

2x+y/3=10-y+2

3y/2+5x=4x+y-6

{6x + 4y = 36

{1y + 2x = -12

1y + 2x = -12 ( isolar 0 (y))

y = -12 - 2x ( substituir o (y))

6x + 4y = 36

6x + 4(-12-2x) = 36

6x - 48 - 8x = 36

6x - 8x = 36 + 48

- 2x = 84

x = 84/-2

x = - 84/2

x = - 42 ( achar o valor de (y))

y = - 12 - 2x

y = - 12 - 2(-42)

y = - 12 + 84

y = 72

x = - 42

y = 72

a) 2x+y/3=10-y+2 e y/2=7-x/4 1

{ 2x + y/3 = 10 - y + 2

y

2x + ----- = 10 - y + 2 ( mmc = 3)

3

3(2x) + 1(y) = 3(10) - 3(y) + 3(2)

----------------------------------------- instrução acima

3

3(2x) + 1(y) = 3(10) - 3(y) + 3(2)

6x + 1y = 30 - 3y + 6

6x + 1y + 3y = 30 + 6

6x + 4y = 36

{y/2=7-x/4 1?????( ESSE (1) ????

y x mmc 2,4| 2

---- = 7 - ------- 1,2| 2

2 4 1,1/ = 2x2 = 4

2(y) = 4(7) - 1(x)

-------------------- instrução acima

4

2(y) = 4(7) - 1(x)

2y = 28 - 1x

2y + 1x = 28

2x+y/3=10-y+2 e y/2=7-x/4 1

{6x + 4y = 36

{ 2y + 1x = 28

2y + 1x = 28 ( isolar o (x))

1x = 28 - 2y ( substituir o (x))

6x + 4y = 36

6(28 - 2y) + 4y = 36

168 - 12y + 4y = 36

- 12y + 4y = 36 - 168

- 8y = - 132

y = - 132/-8

y = + 132/8 (divide AMBOS por 4)

y = 33/2 ( achar o valor de (x))

1x = 28 - 2y

1x = 28 - 2(33/2)

x = 28 - 66/2

66 mmc= 2

x = 28 - -------

2

2(28) - 1(66)

x = ---------------

2

56 - 66

x = -----------------

2

x = - 10/2

x = - 5

x = - 5

y = 33/2

b) 3y/2+5x=4x+y-6 e y+x/2= x/4

{ 3y/2 + 5x = 4x + y - 6

3y

------ + 5x = 4x + y - 6 mmc = 2

2

1(3y) + 2(5x) = 2(4x) + 2(y) - 2(6)

-------------------------------------------- instrução acima

2

1(3y) + 2(5x) = 2(4x) + 2(y) - 2(6)

3y + 10x = 8x + 2y - 12

3y - 2y + 10x - 8x = -12

1y + 2x = -12

y+x/2= x/4

x x

y + ---- = ------ mmc = 4

2 4

4(y) + 2(x) = 1(x)

--------------------- idem acima

4

4(y) + 2(x) = 1(x)

4y + 2x = 1x

4y + 2x - 1x = 0

4y + 1x = 0

3y/2+5x=4x+y-6 e y+x/2= x/4

{ 1x + 2y = - 12

{ 4y + 1x = 0

4y + 1x = 0 ( isolar o (x))

1x = - 4y ( substituir o (x))

1x + 2y = - 12

(-4y) + 2y = -12

-4y + 2y = -12

-2y = - 12

y = -12/-2

y = + 12/2

y = 6 ( achar o valor de (x))

1x = - 4y

1x = -4(6)

x = - 24

x = - 24

y = 6