Question

-42+15=15-2x

-3x+7=-7+4x

3(x+1)=6

4(x+1)=-7x-7

5(y-1)=2y+7

3(x+2)=2(x+4)

-2=5(x+1)-7

6=4(x+1)-2(x+2)


Va rog ajutati-ma!!!! Va dau 15 puncte!!

Answer 1

Răspuns:

Explicație pas cu pas:

- 42+15=15-2x

- 27 = 15 - 2x

- 27 - 15 = - 2x

- 42 = - 2x

x = - 42 : (-2)

x = 21

-3x+7=-7+4x

-3x - 4x = - 7 - 7

- 7x = - 14

x = -14 : (-7)

x = 2

3(x+1)=6

x + 1 = 6 : 2

x + 1 = 3

x = 3 - 1

x = 2

4(x+1)=-7x-7

4x + 4 = - 7x - 7

4x + 7x = - 7 - 7

11x = - 11

x = - 11 : 11

x = - 1

5(y-1)=2y+7

5y - 5 = 2y + 7

5y - 2y = 7 + 5

3y = 12

y = 12 : 3

y = 4

3(x+2)=2(x+4)

3x + 6 = 2x + 8

3x - 2x = 8 - 6

x = 2

-2=5(x+1)-7

-2 = 5x + 5 - 7

- 2 = 5x - 2

-2 + 2 = 5x

0 = 5x

x = 0

6=4(x+1)-2(x+2)

6 = 4x + 4 - 2x - 4

6 = 2x

x = 6 : 2

x = 3