Question

x ПОМОГИТЕ ПОЖАЛУЙСТА

Answer 1

Ответ:

а) х = 6

б) х = 1/7

в) х = 2 74/75    

Пошаговое объяснение:

а) (х-3) * 2/3 = 2

х = 2 : 2/3 +3

х = 2 * 3/2 + 3

х = 6

(6-3) * 2/3 = 3 * 2/3 = 2 - верно

б) 3 1/2 * (2/3х + 4/7) = 2 1/3

2/3х = 2 1/3 : 3 1/2 - 4/7

2/3х = 7/3 * 2/7 - 4/7

2/3х = 2/3 - 4/7 = 14/21 - 12/21

2/3х = 2/21

х = 2/21 : 2/3

х = 2/21 * 3/2

х = 1/7

3 1/2 * (2/3 * 1/7 + 4/7) = 7/2 * (2/21 + 4/7) = 7/2 * 14/21 = 7/3 = 2 1/3 - верно

в) (5/8х - 1/5) * 3/4 = 1 1/4

5/8х = 1 1/4 : 3/4 + 1/5

5/8х = 5/4 * 4/3 + 1/5 = 5/3 + 1/5

5/8х = 28/15

х = 28/15 : 5/8

х = 28/15 * 8/5 = 224/75

х = 2 74/75          

(5/8*2 74/75 - 1/5) * 3/4 = (5/8 * 224/75 - 1/3) * 3/4 =

(28/15 - 1/5) * 3/4 = 5/3 * 3/4 = 5/4 = 1 1/4 - верно