Respuesta :

D. x < 6 represents the solution set of the inequality.

Answer:  [D]:  " x  <  6 " .

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Step-by-step explanation:

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Given:  

 " 5x - 9 < 21 " ;  

→ Add  "9" to each side of the "inequality" ;

" 5x - 9 + 9 < 21 + 9 " ;

→ to get:

" 5x < 30 " ;

Now, divide each side of the "inequality" by "5" ;

 to isolate "x" on one side of the "inequality" ; as follows:

     " 5x / 5  <  30 / 5 "  ;

to get:

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     →   " x  <  6 " .

     →  which is:  Answer choice:  [D]:   " x  <  6 " .

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Hope this is helpful to you!

   Best wishes!

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