Question

Tìm x thuộc Z biết: 

156:(7x+135):x=13

mn giúp em vs ạ em đang cần gấp

Answer 1

Ta có :  \(156:\left(7x+135\right):x=\frac{156}{\frac{7x+135}{x}}=156.\frac{x}{7x+135}\)

\(\Rightarrow156.\frac{x}{7x+135}=13\)

\(\Rightarrow\frac{x}{7x+135}=\frac{13}{156}\)

\(\Rightarrow\frac{x}{7x+135}=\frac{1}{12}\)

\(\Rightarrow12x=7x+135\)

\(\Rightarrow5x=135\)

\(\Rightarrow x=27\)

Answer 2

\(156:\left(7x+135\right):x=13\)

\(\left(7x+135\right):x=12\)

\(7x+135=12x\)

\(7x-12x=-135\)

\(-5x=-135\)

\(x=\frac{-135}{-5}\)

\(x=27\)

hok tốt!!

Answer 3

TRL: 156 : ( 7x + 135 ) : x = 13

         ( 7x + 135 ) : x = 156 : 13 = 12

         7x + 135          = 12x

         7x - 12x           = -135

          -5x                 =   -135

             x                 =  -135 : (-5)

             x                 =       27

Answer 4

156 : ( 7x + 135 ) : x = 13

<=> ( 7x + 135 ) : x  = 12

<=> 7x + 135            =12x

<=> 7x + 12x            = 135

<=> -5x                     = -135

<=> x                        = -135 : ( -5 )

<=> x                        = 27

Vậy :................