800=x+175/5+30

770=x+175/5

x+175=3850

x=22

Ta có: 

a)   (285  - x - 0,15 ) : 0,25 = 15 : 0,25

     (285  - x - 0,15 ) = 15 

      284,85 - x = 15

       x = 284,85 - 15

       x = 269,85

269,85

dễ mà 460 + 85 * 4 = x + 175 : 5 + 30

          460 + 340    = x + 35 + 30

              800         = x + 65

           800 - 65 = x

             735     = x hay x = 735

đề sai bạn ơi

\(420+65\times4=\frac{x+175}{5}+30\)

\(\frac{x+175}{5}=420+260-30\)

\(\frac{x+175}{5}=650\)

\(x+175=650\times5\)

\(x+175=3250\)

x = 3250 - 175

x = 3075

a)420+65x4=(x+175):5+30

420+260=(x+175):5+30

680=(x+175):5+30

680-30=(x+175):5

650=(x+175):5

650x5=x+175

3250=x+175

x=3250-175

x=3075

460+85x4=(x+175):5+30

<=>460+340=x.1/5+175.1/5+30

<=>800=1/5x+35+30

<=>735=1/5.x

<=>x=3675

Chúc bạn học tốt ^_^

460 + 85 x 4 = ( x+ 175 ) : 5 + 30

= 460 + 340 = ( x + 175 ) : 5 + 30

= 800 = ( x + 175 ) : 5 + 30

= ( x + 175 ) : 5 = 800 - 30

= ( x+ 175 ) : 5 = 770

= ( x +175 )       = 770 x 5

= x + 175            = 3850

           x              = 3850 - 175

           x               =  3675

460+85x4=x+175:5+30

460 + 340 = x + 35 + 30

800 = x + 65 

x = 800 - 65

x = 735

460 + 340 = x + 35 + 30

800 = x + 65 

x = 800 - 65

x = 735

460+85x4=(x+175):5+30

<=>460+340=x.1/5+175.1/5+30

<=>800=1/5x+35+30

<=>735=1/5.x

<=>x=3675

Chúc bạn học tốt ^_^