các bạn có biết ( x + 3 ) + ( x + 5 ) + ( x+ 7 ) + ... + ( x + 45 ) = 1210 ko

nếu biết bảo cho tớ nhé tớ đang cần gấp bài này

0.5x - 2/3x = 7/12

<=> 1/2x - 2/3x = 7/12

<=> (1/2 - 2/3).x = 7/12

<=> -1/6.x = 7/12

<=> x = 7/12 : -1/6

<=> x = -7/2

Vậy x = -7/2

x.(0,5-2/3)=7/12

x.-1/6      =7/12

x            =7/12:-1/6

x            = -7/2

k mk nha bạn!! thanks nhìu!!

\(\Leftrightarrow\dfrac{1}{2}x-\dfrac{3}{7}=\dfrac{8}{7}\cdot\dfrac{1}{2}=\dfrac{4}{7}\\ \Leftrightarrow\dfrac{1}{2}x=1\Leftrightarrow x=2\)

(0,5 . x - 3/7) : 1/2 = 1_1/7

(0,5 . x - 3/7) : 1/2 = 8/7

(0,5 . x - 3/7) = 8/7 . 1/2

(0,5 . x - 3/7) = 4/7

0,5 . x = 4/7 + 3/7

0,5 . x = 1

x = 1 : 0,5

x = 2

a) 1/2x - 2/3x = 7/12

    -1/6x = 7/12

     x = \(\frac{7}{12}\div\frac{-1}{6}\)

     x = -7/2

b)  x: 12 = -2,5

     x = -2,5*12

     x = -30

c) 11/2x = 13/15

    x = 13/15:11/2

    x = 26/165

d) 3x/7 + 1 = (-1/28)*(-4)

    3x/7 + 1 = 1/7

    3x/7 = 1/7 - 1

    3x/7 = -6/7

    3x = -6

    x= -6/3

    x= -2

a) x(0.5 - 2/3 ) = 7/12

        (-1/6)x = 7/12

             x      = 7/12 : (-1/6)

            x      =-7/2

b) x :  12 = -2,5

   x= -2.5 * 12  =-30

c)   x = 13/15 : 5,5

    x  =26/125

d) 3x/7 + 1  =  -1/28 * (-4)

   3x/7 + 1   =1/7

  3x/7    = 1/7 -1

   3x/7  =-6/7

   3x    =-6/7 * 7 

  3x = -6

   x =-2

hsssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssss

bạn làm kiểu này :

0.5x-\(\dfrac{2}{3}\)x=\(\dfrac{7}{6}\)

0-\(\dfrac{2}{3}\)x=\(\dfrac{7}{6}\)

\(\dfrac{2}{3}\)x=0-\(\dfrac{7}{6}\)

0.5x-\(\dfrac{2}{3}\)x=\(\dfrac{7}{6}\)

\(\left(\dfrac{1}{2}-\dfrac{2}{3}\right)\). x=\(\dfrac{7}{6}\)

\(\left(\dfrac{3}{6}-\dfrac{4}{6}\right)\). x=\(\dfrac{7}{6}\)

\(\dfrac{-1}{6}\). x=\(\dfrac{7}{6}\)

x=\(\dfrac{7}{6}\):\(\dfrac{-1}{6}\)

x=\(\dfrac{7}{6}\) . \(\dfrac{6}{-1}\)

x=\(\dfrac{42}{-6}\)

x=\(\dfrac{7}{-1}\)

lại bí rùi