Question

Tìm X:

\(\dfrac{25+X}{49+X}\)=\(\dfrac{3}{5}\)

Answer 1

\(\left(25+x\right)\times5=\left(49+x\right)\times3\)

\(125+5x-147-3x=0\)

\(-22+2x=0\)

\(x=11\)

Answer 2

`(25+x)/(49+x)=3/5`

`=>5(25+x)=3(49+x)`

`=>125+5x=147+3x`

`=>5x-3x=147-125`

`=>2x=22`

`=>x=22:2`

`=>x=11`

Vậy `x=11`

Answer 3

\(\dfrac{25+X}{49+X}=\dfrac{3}{5}\\ =>25+X=\dfrac{3}{5}\cdot\left(49+X\right)\\ < =>25+X=\dfrac{147}{5}+\dfrac{3}{5}X\\ < =>X-\dfrac{3}{5}X=\dfrac{147}{5}-25\\ < =>\dfrac{2}{5}X=\dfrac{22}{5}\\ < =>X=\dfrac{22}{5}:\dfrac{2}{5}=11\)