ai nhanh tui tik cho

Đáp án:

`a)` `( 2 4/5 x -50 ) : 2/3 =51`

`<=> ( 14/5 x -50 ) : 2/3 = 51`

`<=> 14/5 x - 50 = 51 xx 2/3`

`<=> 14/5 x -50 =34`

`<=> 14/5 x = 34 + 50`

`<=> 14/5 x = 84`

`<=> x=  84 : 14/5 `

`<=> x=30`

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`b)` `2/3 x -1/2 x =5/12`

`<=> x ( 2/3 -1/2) = 5/12`

`<=> 1/6 x=5/12`

`<=>x= 5/2`