Answer:   " x  =  7 " .
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Step-by-step explanation:
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Given:
x + (2/7)x = 9 ;  Solve for "x" ;
Note: 
Start by simplifying the "left hand side of the equation:
  
 ;
 ; 
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Now, rewrite the equation:
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     ;    Solve for "x" ;
 ;    Solve for "x" ; 
We now multiply each side of the equation by "7" ; 
 to get rid of the "denominator" within the "fraction value" 
   on the "left-hand side" of the equation:
    ;
  ; 
On the "left-hand side" of the equation: 
  The "7's" cancel out to "1's" ;  since "7÷7 = 1 " ; 
    And we are left with "9x" on the "left-hand side" of the equation.
On the "right-hand side" on the equation; we find that: "9 * 7 = 63 ." 
    So; we can rewrite the equation:
           9x = 63 ; 
 To solve for "x" ; we divide each side of the equation by:  "9" ; 
        to isolate "x" on one side of the equation;  
          & to solve for "x" ; 
           9x / 9 = 63 / 9 ; 
to get: 
               x  =  7 .
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Hope this answer—and explanation—is helpful!
   Best wishes to you!
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