document.write( "Question 1198731: Consider the equation, 4x^2-18x=3. What number must be added to both sides of the equation in order to complete the square? \n" ); document.write( "

Algebra.Com's Answer #832368 by ikleyn(52790) $\"\"$ $\"About$

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\n" ); document.write( "Consider the equation, 4x^2-18x=3. What number must be added
\n" ); document.write( "to both sides of the equation in order to complete the square?
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document.write( "The leading term with  x^2  is  4x^2 = (2x)^2.\r\n" );
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document.write( "Therefore, you should add the term c^2, where you determine the value of \"c\" \r\n" );
document.write( "from this equality\r\n" );
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document.write( "    2*(2c) = -18,  which gives  c =  = -4  = -4.5.\r\n" );
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document.write( "The term to add to both sides is (-4.5)^2 = 20.25.    ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "On solving quadratic equations using completing the square method, look into the lesson\r
\n" ); document.write( "\n" ); document.write( " - HOW TO solve quadratic equation by completing the square - Learning by examples \r
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\n" ); document.write( "\n" ); document.write( "What Alan recommends in his post, is incorrect.\r
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document.write( "The correct addend is  ,  referring to the general equation form\r\n" );
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document.write( "    ax^2 + bx = -c.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Do not even read the post by @MathLover1, if you want to save your mind,\r
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\n" ); document.write( "\n" ); document.write( "since her recommendation is totally wrong: it relates to the modified leading part equation,\r
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\n" ); document.write( "\n" ); document.write( "while the problem asks about the addend to UNMODIFIED leading part equation.\r
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