document.write( "Question 141031: I want to solve $\"x%5E2%2B3x-4=0\"$ by \"completing the square\", I have a textbook and some animations but I just do not get it. I had a problem with quadratic formula and I found an example on this website that just made that click for me. I am hoping someone can do the same with \"complete the square\". Thanks in advance for you explanation. \n" ); document.write( "

Algebra.Com's Answer #102680 by stanbon(75887) $\"\"$ $\"About$

You can put this solution on YOUR website!
solve $\"x%5E2%2B3x-4=0\"$ by \"completing the square\",
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\n" ); document.write( "x^2+3x+? = 4+?
\n" ); document.write( "Square [(1/2)3] and add it to the left and right side to get:\r
\n" ); document.write( "\n" ); document.write( "x^2+3x + [(1/2)3]^2 = 4 + [(1/2)3]^2\r
\n" ); document.write( "\n" ); document.write( "Simplify both sides:\r
\n" ); document.write( "\n" ); document.write( "(x+(3/2))^2 = 4 + (3/2)^2\r
\n" ); document.write( "\n" ); document.write( "(x+(3/2))^2 = 25/4\r
\n" ); document.write( "\n" ); document.write( "Take the square root of both sides to get:\r
\n" ); document.write( "\n" ); document.write( "(x+(3/2)) = +- 5/2\r
\n" ); document.write( "\n" ); document.write( "x = (-3/2) + (5/2) or x = (-3/2) - (5/2)\r
\n" ); document.write( "\n" ); document.write( "x = 1 or x = 4
\n" ); document.write( "=====================
\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H. \n" ); document.write( "

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