PILNE !!!

metodą PRZECIWNYCH WSPÓŁCZYNNIKÓW(Jeśli chodsz do 2 gim. i Masz podr.MATEMATYKA Z PLUSEM to to jest zad.10/97 ) ALE KONIECZNIE METODĄ PRZECIWNYCH WSPÓŁCZYNNIKÓW.!

a. y+2-(3-x)=0
x-2=5-(2-y)



b. 3(x-y)+4x=8
3(x-5y)=5-9y



c. 3(2x-1)+4(y-2)=9
2(5x-1)+3y=5(3x+y)+2



d. 2(x+y)-3(x-2y)=-7x-2
5(x+1)-2(3-y)=-4(x+y)


e. 4(x+2)-3(y-1)=x+y-3
3(x-4)-2(y-2)=4(x-y)+4

NAJLEPSZE BARDZO DOBRZE WYNAGRADZAM ;-)
jesli będzie dużo błędów uznaje z błędne;p

3

Odpowiedzi

Najlepsza Odpowiedź!
2009-12-10T21:53:36+01:00
A. y+2-(3-x)=0
x-2=5-(2-y)

y + 2 - 3 + x = 0
x - 2 = 5 - 2 +y

x + y = 1
x - y = 5

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

x = 3
y = -2

b. 3(x-y)+4x=8
3(x-5y)=5-9y

3x - 3y + 4x = 8
3x - 15y = 5 - 9y

7x - 3y = 8 /×(-2)
3x - 6y = 5

-14x + 6y = -16
3x - 6y = 5

-11x = -11
x = 1
3 - 6y = 5
y = -1/3

c. 3(2x-1)+4(y-2)=9
2(5x-1)+3y=5(3x+y)+2

6x - 3 + 4y - 8 = 9
10x -2 +3y = 15x + 5y + 2

6x + 4y = 20
-5x - 2y = 4/ x2

6x + 4y = 20
-10x - 4y = 8

-4x = 28
x = -7
-42 + 4y = 20
y = 15,5

d. 2(x+y)-3(x-2y)=-7x-2
5(x+1)-2(3-y)=-4(x+y)

2x + 2y - 3x + 6y = -7x - 2
5x + 5 - 6 + 2y = -4x - 4y

6x + 8y = -2 / ×(-3)
9x + 6y = 1 / ×2

-18x - 24y = 6
18x + 12y = 2

-12y = 8
y = -2/3
9x - 4 = 1
x = 5/9

e. 4(x+2)-3(y-1)=x+y-3
3(x-4)-2(y-2)=4(x-y)+4

4x + 8 - 3y + 3 = x + y - 3
3x - 12 - 2y + 4 = 4x - 4y + 4

3x - 4y = -14
-x + 2y = 12 /×2

3x - 4y = -14
-2x + 4y = 24

x = 10
-20 + 4y = 24
y = 11
2009-12-11T02:05:41+01:00
A.
y + 2 - (3 - x) = 0
x - 2 = 5 - (2 - y)

y + 2 - 3 + x = 0
x - 2 = 5 - 2 + y

x + y = 1
x - y = 5

2x = 6 |:2
x = 3

x = 3
3 + y = 1

x = 3
y = -2


b.
3(x - y) + 4x = 8
3(x - 5y) = 5 - 9y

3x - 3y + 4x = 8
3x - 15y = 5 - 9y

7x - 3y = 8 |*(-2)
3x - 6y = 5

-14x + 6y = -16
3x - 6y = 5

-11x = -11 |:(- 11)
x = 1

x = 1
3*1 - 6y = 5

x = 1
-6y = 5 - 3

x = 1
-6y = 2 |:(-6)

x = 1
y = -⅓

c.
3(2x - 1) + 4(y - 2) = 9
2(5x - 1) + 3y = 5(3x + y) + 2

6x - 3 + 4y - 8 = 9
10x -2 +3y = 15x + 5y + 2

6x + 4y = 20 |:2
-5x - 2y = 4

3x + 2y = 10
-5x - 2y = 4

-2x = 14 |:(-2)
x = -7

x = -7
-21 + 2y = 10

x = -7
2y = 31 |:2

x = -7
y = 15,5

d.
2(x + y) - 3(x - 2y) = - 7x - 2
5(x + 1) - 2(3 - y) = - 4(x + y)

2x + 2y - 3x + 6y = -7x - 2
5x + 5 - 6 + 2y = -4x - 4y

6x + 8y = -2 |*3
9x + 6y = 1 |*(-2)

18x + 24y = - 6
- 18x - 12y = - 2

12y = - 8 |:12
y = - ⅔

9x + 6*(- ⅔) = 1
y = - ⅔

9x - 4 = 1
y = - ⅔

9x = 5 |:9
y = - ⅔

x = 5/9
y = - ⅔

e.
4(x + 2) - 3(y - 1) = x + y - 3
3(x - 4) - 2(y - 2) = 4(x - y) + 4

4x + 8 - 3y + 3 = x + y - 3
3x - 12 - 2y + 4 = 4x - 4y + 4

3x - 4y = -14
-x + 2y = 12 |*3

3x - 4y = -14
-3x + 6y = 36

2y = 22 |:2
y = 11

3x - 4 * 11 = -14
y = 11

3x = 30 |:3
y = 11

x = 10
y = 11
2009-12-11T02:11:04+01:00
A. y+2-(3-x)=0
x-2=5-(2-y)

y+2-3+x=0
x-2=5-2+y

x+y=1
x-y=5
------------
2x=6 /:2
x=3

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

Odp.
x=3
y=-2



b. 3(x-y)+4x=8
3(x-5y)=5-9y

3x-3y+4x=8
3x-15y=5-9y

7x-3y=8 /*(-2)
3x-6y=5

-14x-6y=-16
3x-6y=5
------------
-11x=-11 /:(-11)
x=1

3x-6y=5
3-6y=5
-6y=5-3
-6y=2 /:(-6)
y=-2/6
y=-1/3

Odp.
x=1
y=-1/3

c. 3(2x-1)+4(y-2)=9
2(5x-1)+3y=5(3x+y)+2

6x-3+4y-8=9
10x-2+3y=15x+5y+2

6x+4y=9+11
10x-15x+3y-5y=2+2

6x+4y=20 /:2
-5x-2y=4

3x+2y=10
-5x-2y=4
------------
-2x=14 /:(-2)
x=-7

3x+2y=10
3*(-7)+2y=10
-21+2y=10
2y=10+21
2y=31 /:2
y=15,5

Odp.
x=-7
y=15,5

d. 2(x+y)-3(x-2y)=-7x-2
5(x+1)-2(3-y)=-4(x+y)

2x+2y-3x+6y=-7x-2
5x+5-6+2y=-4x-4y

-x+7x+8y=-2
5x+4x+2y+4y=1

6x+8y=-2 /:2
9x+6y=1

3x+4y=-1 /*(-3)
9x+6y=1

-9x-12y=3
9x+6y=1
-------------
-6y=4 /:(-6)
y=-4/6
y=-2/3

9x+6y=1
9x+6(-2/3)=1
9x-4=1
9x=1+4
9x=5 /:9
x=5/9

Odp.
x=5/9
y=-2/3

e. 4(x+2)-3(y-1)=x+y-3
3(x-4)-2(y-2)=4(x-y)+4

4x+8-3y+3=x+y-3
3x-12-2y+4=4x-4y+4

4x-x-3y-y=-3-11
3x-4x-2y+4y=4+8

3x-4y=-14
-x+2y=12 /*2

3x-4y=-14
-2x+4y=24
-----------------
x=10

-x+2y=12
-10+2y=12
2y=12+10
2y=22 /:2
y=11

Odp.
x=10
y=11