X.1999.X=1999.1997+1999

X.1999.X=1999.1997+1999.1

X.X.1999=1999.(1997+1)

X.X.1999=1999.1998

X.X=1999.1998:1999=1998

 X × 1999 × X = 1999 × 1997 + 1999

X^2 x 1999 = 1999 × 1997 + 1999 x 1

X^2 x 1999 = 1999 x ( 1997 + 1 )

X^2 x 1999 = 1999 x 1998

X^2 = 1999 x 1998 : 1999

X^2 = 1999 : 1999 x 1998

X^2 = 1 x 1998

X^2 = 1998

a , x = 501

b , x = 1999

a) 5 * x - 1952 = 2500 - 1947

    5 * x -1952 =553

    5 * x             = 553 + 1952

    5 * x             =2505

    x                   = 501

b)x * 1999 - x = 1999*1997 +1999

 x * ( 1999 -1) = 1999*(1997 +1)

 x * 1998          =1999 * 1998

x                        =1999

X x 1999 - x = 1999 x 1997 + 1999

X x (1999 - 1) = 1999 x (1997 + 1)

X x 1998 = 1999 x 1998

Vậy x = 1999

2x1999-5=1999x1999+1999

x=1999

nha

x=1999

X * 1999 - x = 1999 x 1997 + 1999

X * 1998      = 1999 x 1998

=> x = 1999

1999x-(-x)=1999.1997+1999

<=>2000x=3994002

<=>x=1997,001

x * 1999 = 1999* 1997 + 1999

x * 1999 = 1999 * 1998

Từ đây ta suy ra x = 1998

x.1999 - x = 1999.1997 + 1999

x.(1999 - 1) = 1999.(1997 + 1)

x.1998 = 1999.1998

=> x = 1999

Vậy x = 1999

Ủng hộ mk nha ☆_☆^_-

X . 1999 - x = 1999 x 1997 + 1999

X . 1999 - X x 1 = 1999 x 1997 + 1999 x 1

X . 1997 = 1999 x 1998

X . 1997 = 3994002

X = 3994002 : 1997

X = 1997001

x . 1999 - x = 1999 . 1997 + 1999

=> x.(1999 - 1) = 1999.(1997 + 1)

=> x.1998 = 1999.1998

=> x = 1999

vậy x = 1999

Dấu . là nhân nha

X x 1999 - x = 1999 x 1997 + 1999

X x 1999 - X x 1 = 1999 x 1997 + 1999 x 1

X x (1998 - 1) = 1999 x (1997 + 1)

X x 1997 = 1999 x 1998

X x 1997 = 3994002

X = 3994002 : 1997

X = 1997001

x*2000-x=1999-1997

x*2000-x*1=2

x*(2000-1)=2

x*1999=2

x          =2:1999

x         =2/1999

x . 2000 - x = 1999 . 1997

x . ( 2000 - 1 ) = 1999 . 1997

x . 1999 = 1999 . 1997

x = 1997

X x 2000 - x = 1999 x 1997

X x 1999      = 3992003

X                  = 3992003 : 1999

X                   = 1997

Cái câu X x 1999 mk làm vậy là vì 2000 lần x - 1 lần x = 1999 lần x nhé !

Kb vs mk và tk mk nha !! ^^