document.write( "Question 715877: Completing the square. This is so difficult. Can someone show me easy steps to understand this.\r
\n" ); document.write( "\n" ); document.write( "1.)4x^2+x+3=0
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Algebra.Com's Answer #439646 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!

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Solved by pluggable solver: Completing the Square to Get a Quadratic into Vertex Form

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\n" ); document.write( " \"y=4+x%5E2%2B1+x%2B3\" Start with the given equation
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\n" ); document.write( " \"y-3=4+x%5E2%2B1+x\" Subtract \"3\" from both sides
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\n" ); document.write( " \"y-3=4%28x%5E2%2B%281%2F4%29x%29\" Factor out the leading coefficient \"4\"
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\n" ); document.write( " Take half of the x coefficient \"1%2F4\" to get \"1%2F8\" (ie \"%281%2F2%29%281%2F4%29=1%2F8\").
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\n" ); document.write( " Now square \"1%2F8\" to get \"1%2F64\" (ie \"%281%2F8%29%5E2=%281%2F8%29%281%2F8%29=1%2F64\")
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\n" ); document.write( " \"y-3=4%28x%5E2%2B%281%2F4%29x%2B1%2F64-1%2F64%29\" Now add and subtract this value inside the parenthesis. Doing both the addition and subtraction of \"1%2F64\" does not change the equation
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\n" ); document.write( " \"y-3=4%28%28x%2B1%2F8%29%5E2-1%2F64%29\" Now factor \"x%5E2%2B%281%2F4%29x%2B1%2F64\" to get \"%28x%2B1%2F8%29%5E2\"
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\n" ); document.write( " \"y-3=4%28x%2B1%2F8%29%5E2-4%281%2F64%29\" Distribute
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\n" ); document.write( " \"y-3=4%28x%2B1%2F8%29%5E2-1%2F16\" Multiply
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\n" ); document.write( " \"y=4%28x%2B1%2F8%29%5E2-1%2F16%2B3\" Now add \"3\" to both sides to isolate y
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\n" ); document.write( " \"y=4%28x%2B1%2F8%29%5E2%2B47%2F16\" Combine like terms
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\n" ); document.write( " Now the quadratic is in vertex form \"y=a%28x-h%29%5E2%2Bk\" where \"a=4\", \"h=-1%2F8\", and \"k=47%2F16\". Remember (h,k) is the vertex and \"a\" is the stretch/compression factor.
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\n" ); document.write( " Check:
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\n" ); document.write( " Notice if we graph the original equation \"y=4x%5E2%2B1x%2B3\" we get:
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\n" ); document.write( " \"graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C4x%5E2%2B1x%2B3%29\" Graph of \"y=4x%5E2%2B1x%2B3\". Notice how the vertex is (\"-1%2F8\",\"47%2F16\").
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\n" ); document.write( " Notice if we graph the final equation \"y=4%28x%2B1%2F8%29%5E2%2B47%2F16\" we get:
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\n" ); document.write( " \"graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C4%28x%2B1%2F8%29%5E2%2B47%2F16%29\" Graph of \"y=4%28x%2B1%2F8%29%5E2%2B47%2F16\". Notice how the vertex is also (\"-1%2F8\",\"47%2F16\").
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\n" ); document.write( " So if these two equations were graphed on the same coordinate plane, one would overlap another perfectly. So this visually verifies our answer.
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