Tìm x, y a) x + 5/4 = ( 3/2 )^ 2 b) 3/4 + 2/5x = 19/20 c) (1/3x) : 2/3 = 1 1/3 : 2/5 d) 8: ( 1/4x ) = 2:0,02

Giải thích các bước giải:

$a)$ `x +5/4 = (3/2)²`

`⇒ x = 9/4 -5/4`

`⇒ x = 1`

Vậy `x = 1`

—————-

$b)$ `3/4 +2/5x = 19/20`

`⇒ 2/5x = 1/5`

`⇒ x = 1/5 : 2/5`

`⇒ x = 1/2`

Vậy `x = 1/2`

—————-

$c)$ `(1/3x) : 2/3 = 1 3/4 : 2/5`

`⇒ 1/3x = 35/8 . 2/3`

`⇒ 1/3x = 35/12`

`⇒ x = 35/4`

Vậy `x = 35/4`

—————-

$d)$ `8: ( 1/4x ) = 2 : 0,02`

`⇒ 1/4x = 8 :100`

`⇒ 1/4x = 0,08`

`⇒ x = 0,32`

Vậy `x = 0,32`