Question

rozwiąż równania a)3-4x=8-3x b) 3x-5=8-3x c)3y-4=8y d)5y+1=2y-5 e)a-18=12 f)2a+3=a-2 g)3a-7=7a+3 DO KAŻDEGO SPRAWDZENIE.!!!

Answer 1

a)

-4x+3x=8-3

-x=5/*(-1)

x=-5

spr.

3+20=8+15

23=23

b)

6x=13/:6

x=13/6

spr.

39/6-5=8-39/6

39/6-30/6=48/6-39/6

9/6=9/6

c)

-4=5y

y=-4/5

spr.

-12/5-20/5=-32/5

d)

3y=-6/:3

y=-2

spr.

-10+1=-4-5

-9=-9

e)

a=12+18=30

spr.

30-18=12

12=12

f)

a=-2-3

a=-5

spr.

-10+3=-5-2

-7=-7

g)

-4a=10/:(-4)

a=-2,5

spr.

-7,5-7=-17,5+3

-14.5=-14,5

Answer 2

a)

3-4x=8-3x

-4x +3x = 8-3

-x = 5  /*(-1)

x= -5

Spr.

3 – 4 * (-5) = 8 – 3 *(-5)

3+20 = 8 +15

23 = 23

L=P

 

 b)

 3x-5=8-3x

3x+3x = 8 +5

6x = 13  /:6

x = 13/6

spr.

3*13/6 – 5 = 8 – 3 * 13/6

13/2 -5 = 8 – 13/2

 1 ½  = 1 ½

L=P

 

c)

3y-4=8y

8y -3y = -4

5y = -4   / :5

y = -4/5

spr.

3*(-4/5) – 4 = 8 *(-4/5)

-12/5 – 4 = -32/5

-12/5 – 20/5 = -32/5

-32/5 = -32/5

L=P

 

d)

5y+1=2y-5

5y -2y = -5 -1

3y = -6   /: 3

y = -2

spr.

5*(-2) +1 = 2 *(-2) -5

-10 +1 = -4-5

-9 = -9

L=P

 

e)

a-18=12

a= 12+18

a = 30

spr.

30 -18 = 12

12=12

L=P

 

 f)

2a+3=a-2

2a – a =  -2-3

a = -5

spr.

2*(-5) + 3 = -5-2

-10 +3 = -7

-7 = -7

L=P

 

g)

3a-7=7a+3

7a – 3a = -7 -3

4a = -10  /:4

a = -10/4

a = -5/2

spr.

3*(-5/2) – 7 = 7 *(-5/2) + 3

-15/2 – 7 = -35/2 + 3

-15/2 – 14/2 = -35/2 +6/2

-29/2 = -29/2

L=P