Answer: [D]: " x < 6 " .
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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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