Question

Giúp em với

Answer 1

`A=7/3 - (3/5 + 1/a) : 2/3`

Thay `a=45`

`=> 7/3 - (3/5+1/45):2/3`

`=7/3 - (27/45 + 1/45):2/3`

`=7/3 - 28/45 : 2/3`

`=7/3 - 28/45 . 3/2`

`=7/3 - 14/15`

`=35/15 - 14/15`

`=7/5`

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`7/3 - (3/5+1/a):2/3=17/15`

`(3/5+1/a):2/3 = 7/3 - 17/15`

`(3/5+1/a):2/3 = 35/15 - 17/15`

`(3/5+1/a):2/3 =6/5`

`3/5+1/a = 6/5 xx 2/3`

`3/5+1/a =4/5`

`1/a = 4/5 -3/5`

`1/a = 1/5`

`=> a=5`

Answer 2

`a)`

`A=7/3 -(3/5 +1/a):2/3`

thay `a=45`

`A=7/3 -(3/5 +1/45):2/3`

`A= 7/3 -28/45 : 2/3`

`A= 7/3 -28/45 xx 3/2`

`A= 7/3 -14/15`

`A= 7/5`

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