Answer:  The lengths of the sides of the triangle are: 
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                      " 5 cm, 15 cm, and 10 cm " .
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Step-by-step explanation:
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1x + 3x + 2x = 30 ;  
In which the sides are:
1x ;  3x,  2x ;  
Find:  1x  ; 3x;  and 2x .
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Let us begin by finding "x" :
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1x + 3x + 2x = 30
1x + 3x + 2x = 6x ;  
 →  6x  =   30  ; 
Divide each side of the equation by:  " 6 " ; 
      to isolate "x" on each side of the equation; and to solve for "x" ; 
  →  6x / 6  = 30 / 6 ; 
to get: 
  →   x  =  5  ;
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Now, solve for the length of each side;
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  1x   =     x    =   5 cm ; 
  3x  =   (3*5) =  15 cm ; 
  2x  =   (2*5) =  10 cm ; 
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Answer:  The lengths of the sides of the triangle are: 
                      5 cm, 15 cm, and 10 cm .
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 Hope this helps! 
        Best wishes to you in your academic pursuits
               — and within the "Brainly" community!
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