63 ÷ (5х - 3х - 1) = 21 ÷ 3

40 - 3(х + 2) = 10
, буду благодарна.

63 ÷ (5х - 3х - 1) = 21 ÷ 3

63 ÷ (5х - 3х - 1) = 7

63 ÷ (2х - 1) = 7

63 / 2х - 1 = 7

63 = 7(2х - 1)

9 = 2х - 1

- 2х = -1 -9

- 2х = -10

х = 5

40 - 3(х + 2) = 10

40 - 3х + 2 = 10

34 - 3х = 10

- 3х = 10 - 34

- 3х = - 24

х= 8