Question

Rozwiąż i sprawdź.

1. a - 4 = 2/3 a - 8

2.6 4/5 = 1/7 b - 1/5

Answer 1

1.  a - 4 = 2/3 a - 8

a- 2/3a = -8 + 4

1/3a = -4    obustronnie * 3

a = -12

 

spr.

-12 - 4 = 2/3* (-12) -8

-16 = -16

 

2.  6 4/5 = 1/7 b - 1/5

6 4/5 + 1/5 = 1/7b

7 = 1/7 b    obusronnie *7

49 = b

 

spr.

6 4/5 = 1/7 * 49 - 1/5

6 4/5 = 6 4/5

 

myślę, że pomogłam

 

Answer 2

1.

a - 4 = 2/3 a - 8

3/3a-2/3a = -8+4

1/3a = -4  /*3

a=-12

 

spr.

-12-4 = 2/3*(-12)-8

-16 = -8-8

-16=-16

 

 

2.

6 4/5 = 1/7 b - 1/5

68/10 = 17/10b - 2/10

-17/10b = -2/10 - 68/10

-17/10b = - 70/10   / *(-10/17

b = 70/17 =  4 2/17

 

spr

6 4/5 = 1/7 b - 1/5

6 4/5 = 17/10 * 70/17 - 1/5

6 4/5 = 7 - 1/5

6 4/5 = 35/5 - 1/5

6 4/5 = 34/5

6 4/5 = 6 4/5