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The solution to -2[1 - 4x] = 3x + 8 is

User Yasitha
by
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1 Answer

5 votes

Answer: " 14 " .

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→ " x = 14 " .

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Explanation:

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First, let us simplify the expression on the "left-hand side" of the equation:

→ -2(1 −4x) ;

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Note the "distributive property of multiplication" :

→ a(b + c) = ab + ac .

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As such, we can rewrite:

→ -2(1 − 4x) = (-2)(1) + (-2)(-4x) ;

= - 2 + 8x ;

↔ 8x − 2 ;

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Now, rewrite the entire expression:

→ 8x − 2 = 3x + 8 ;

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Subtract "(3x)" from each side of the equation;

and add "2" to each side of the equation:

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→ 8x − 2 − 3x + 2 = 3x + 8 − 3x + 2 ;

to get:

→ 5x = 10 ;

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

to isolate "x" on side of the equation;

& to solve for "x" ;

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→ 5x/5 = 10/5 ;

to get:

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x = 2 .

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Now, let us check our work:

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Plug in "2" for all "x-values" into the original equation;

to see if the equation holds true;

that is, to see if each side of the original equation given has the same value;

when "x = 2" :

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Note the given equation:

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-2[1 − 4x] = 3x + 8 ;

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Start with the left-hand side:

→ -2[1 − (4*2)} = -2(1 − 8) = -2(-7) = 14 .

Now, continue with the right-hand side:

→ 3(2) + 8 = 6 + 8 = 14 .

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→ 14 =? 14 ??? ; Yes!

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Hope this is helpful to you!

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User Bubla
by
3.9k points