\(180-\left(x-45\right)\div2=120\)

\(\left(x-45\right)\div2=180-120\)

\(\left(x-45\right)\div2=60\)

\(x-45=60\times2\)

\(x-45=120\)

\(x=120+45\)

\(x=165\)

\(\left(2009-x\right)\div29+32=100\)

\(\left(2009-x\right)\div29=100-32\)

\(\left(2009-x\right)\div29=68\)

\(2009-x=68\times29\)

\(2009-x=1972\)

\(x=2009-1972\)

\(x=37\)

\(\left(x-2\right)\times3-270\div45=120\)

\(\left(x-2\right)\times3-6=120\)

\(\left(x-2\right)\times3=120+6\)

\(\left(x-2\right)\times3 =126\)

\(x-2=126\div3\)

\(x-2=42\)

\(x=42+2\)

\(x=44\)

\(\left(x+0,2\right)+\left(x+0,7\right)+\left(x+1,2\right)+...+\left(x+4,2\right)+\left(x+4,7\right)=65,5\)

\(\left(x+x+x+..+x+x\right)+\left(0,2+0,7+1,2+...+4,2+4,7\right)=65,5\)

\(10x+\frac{\left(0,2+4,7\right)\times10}{2}=65,5\)

\(10x+24,5=65,5\)

\(10x=65,5-24,5\)

\(10x=41\)

\(\Rightarrow x=4,1\)

\(e,\left(x-2\right).3-270:45=120\)

\(\Rightarrow\left(x-2\right).3-6=120\)

\(\Rightarrow\left(x-2\right).3=126\)

\(\Rightarrow x-2=42\)

\(\Rightarrow x=44\)

Bài làm

a) 16 . 34 + 66 . 16 - 72 

= 16 . ( 34 + 16 ) - 72

= 16 . 80 - 72

= 1280 - 72

= 1208

b) 4,25 . 58,47 + 125  + 41,53 . 4,25

= 4,25 . ( 58,47 + 41,53 ) + 125

= 4,25 . 100 + 125

= 425 + 125

= 550

c) x : 15 + 42 = 15 + 25 . 8 

    x : 15 + 42 = 15 + 200

    x : 15 + 42 = 215

    x : 15         = 215 - 42

    x : 15         = 173

    x                = 173 . 15

    x                = 188

Vậy x = 188

~ Hai câu cuối làm nốt nha, hết thời gian cho một câu hỏi r. ~

# Học tốt #

#)Giải :

a)\(\left(x-149\right)\div35=270\)

\(\Leftrightarrow x-149=9450\)

\(\Leftrightarrow x=9599\)

\(a,(x-149):35=270\)

\(\Leftrightarrow x-149=9450\)

\(\Leftrightarrow x=9450+149=9599\)

Vậy x = 9599

\(b,(2009-x):29+32=100\)

\(\Leftrightarrow(2009-x):29=68\)

\(\Leftrightarrow2009-x=1972\)

\(\Leftrightarrow x=2009-1972=37\)

Vậy x = 37

\(c,x+472=918\)

\(\Leftrightarrow x=918-472=446\)

Vậy x = 446

a) (x - 149) : 35 = 270

              x - 149 = 270 . 35

               x - 149 = 9450

                        x = 9450 + 149

                        x = 9599

b) (2009 - x) : 29 + 32 = 100

            (2009 - x) : 29 = 100 - 32

            (2009 - x) : 29 = 68

                     2009 - x = 68 x 29

                    2009 - x = 1972

                               x = 2009 - 1972

                               x = 37

c) x + 172 = 918

              x = 918 - 472

              x = 446

mình chịu thôi!lêu...lêu...lêu

( x - 2 ) . 3 - 270 : 45 = 120

( x - 2 ) . 3 - 6 = 120

( x - 2 ) . 3 = 120 + 6

( x - 2 ) . 3 = 126

x - 2 = 126 :3

x - 2 = 42

     x = 42 + 2

     x = 44

Tìm x sao cho : x - 270 / 45 = 120

\(\left(x-2\right)\times3-270:45=120\)

\(\Rightarrow\left(x-2\right)\times3-6=120\)

\(\Rightarrow\left(x-2\right)\times3=120+6\)

\(\Rightarrow\left(x-2\right)\times3=126\)

\(\Rightarrow x-2=126:3\)

\(\Rightarrow x-2=42\)

\(\Rightarrow x=42+2\)

\(\Rightarrow x=44\)

Vậy x = 44

_Chúc bạn học tốt_

\(\left(x-2\right)\cdot3-270:45=120\)

\(\left(x-2\right)\cdot3-6=120\)

\(\left(x-2\right)\cdot3=120+6\)

\(\left(x-2\right)\cdot3=126\)

\(x-2=42\)

\(x=44\)

\(\left(x-2\right).3-6=120\Leftrightarrow\left(x-2\right).3=126\Leftrightarrow x-2=42\Leftrightarrow x=44\)

Trả lời:

(x - 2) x 3 - 270 : 45 = 120

=> (x - 2) x 3 - 6 = 120

=> (x - 2) x 3 = 120 + 6

=> (x - 2) x 3 = 126

=> x - 2 = 126 : 3

=> x - 2 = 42

=> x = 42 + 2

=> x = 44

A, x=9590                D, x=3000 

B, x=165                  E, x=9

C, x=10

bạn chi câu e cho mk kĩ hơn đc k  bảo như

(x-140):35=270

x-140 = 270 x 35

x-140 = 9450

      x = 9450+ 140

      x = 9590

180 - ( x - 45 ) : 2 = 120

180 - ( x- 45)        = 120 x 2

180 - (x - 45)        = 240

           x -45          = 180 - 240

           x - 45          = -60

          x                   = -60 + 45

           x                    = -15

\(\left(x-2\right)\times3-270:45=120\)

\(\Rightarrow3x-6-6=120\)

\(\Rightarrow3x=120+6+6\)

\(\Rightarrow3x=132\)

\(\Rightarrow x=44\)