Tìm x, biết: x - 3/4 = 5/(- 6)

Câu 25:

a) x - 3/4 = 5/ -6

x = 3/4 - 5/6

x = -1/12

b) -2x/3 + 1/2 = 3/4

- 2x/3 = 3/4 - 1/2

- 2x/3 = 1/4

x = 1/4 : -2/3

x = -3/8

Câu 26:

a) x + 5/7 = - 4/9

x = -4/9 - 5/7

x = - 73/63

b) 2x/3 - 3/4 = - 5/12

2x/3 = - 5/12 + 3/4

2x/3 = 1/3

x = 1/2

Câu 27:

4/5 + x = 1/2

x = 1/2 - 4/5

x = -3/10

b) 1/7 - 3x/4 = 3/5

3x/4 = 1/7 - 3/5

3x/4 = - 16/35

x = -64/105