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if the product of 4 and a number is decreased by 12, the result is twice the opposite of the number. Find the number. EXPLAIN PLEASE ♥

1 Answer

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Answer: The number is: "2 " .
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Step-by-step explanation:
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Write the expression; which is an equation, as follows:
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" 4x − 12 = 2(-x) " ; in which "x" represents "the number for which we shall solve" .
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Note:

If the "number" = "x" ; the "opposite of the number" = " -x " ;
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Rewrite as: " 4x − 12 = -2x " ;
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→ Add "12" ; & add "2x" ; to EACH SIDE of the equation:

4x − 12 + 12 + 2x = -2x + 12 + 2x ;

to get: 6x = 12 ;
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Now, divide each side of the equation by "6" ;
to isolate "x" on one side of the equation; & to solve for "x" ;
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6x / 6 = 12 / 6 ;

to get: x = 2 .
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Answer: The number is: "2 " .
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Let us check our answer, by plugging in "2" for "x" in our original equation:
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→ " 4x − 12 = 2(-x) " ;

Let us plug in "2" for "x" ; to see if the equation holds true; that is; if both side of the equation are equal; when "x = 2" ;

→ " 4(2) − 12 = ? 2(-2) ??

→ 8 − 12 = ? -4 ? ;

→ -4 = ? -4 ?? Yes!
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User Gayot Fow
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