Question

a) (2,8x -32) :2/3 = -90

b) 4/5+5/7:x=1/6           tìm x

Answer 1

` (2,8x -32) :2/3 = -90`

`2,8x -32 = -90 xx 2/3`

` 2,8x -32 = -60`

`2,8x = -60 + 32`

`2,8x = -28`

` x = -28 : 2,8`

` x = -10`

______________________

` 4/5 + 5/7 : x = 1/6`

`5/7 : x = 1/6 - 4/5`

`5/7 : x = -19/30`

`x = 5/7 : (-19/30)`

`x = 5/7 xx (-30/19)`

` x = -150/133`

 

`#Lanh`

Answer 2

Tìm x

a) ( 2,8x - 32 ) : 2/3 = -90

( 2,8x - 32 ) = -90 x 2/3

( 2,8x - 32 ) = -60

2,8x = -60 + 32

2,8x = -28

x = -28 : 2,8

x = -10

b) 4/5 + 5/7 : x = 1/6

5/7 : x = 1/6 - 4/5

5/7 : x = -19/30

x = 5/7 : -19/30

x = -150/133.