Respuesta :

The answer is:  " x + 3 " .
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Explanation:
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[tex] \frac{3x+9}{3} [/tex] ;

= [tex] \frac{3x}{3}[/tex] + [tex] \frac{9}{3}[/tex] ;
 
=    x + 3 .
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Note:  An equilateral triangle has 3 SIDES THAT ARE EQUAL IN LENGTH.
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The perimeter is the sum of the total length of all three (3) sides.  So, to find the length of each side {Note: Each side has an equal length}; we divide the given perimeter, by "3"}.

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The answer is:  " x + 3 " .
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To check our answer:

3(x+3) =? 3x + 9 ??

Using the distributive property of multiplication:
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(3*x) + (3*3) =? 3x + 9?

  3x + 9 =? 3x + 9 ?  Yes!
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