document.write( "Question 83726: Graphing Y=x^2+3x+2
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Algebra.Com's Answer #60232 by jim_thompson5910(35256)\"\" \"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=1+x%5E2%2B3+x%2B2\" Start with the given equation
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\n" ); document.write( " \"y-2=1+x%5E2%2B3+x\" Subtract \"2\" from both sides
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\n" ); document.write( " \"y-2=1%28x%5E2%2B3x%29\" Factor out the leading coefficient \"1\"
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\n" ); document.write( " Take half of the x coefficient \"3\" to get \"3%2F2\" (ie \"%281%2F2%29%283%29=3%2F2\").
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\n" ); document.write( " Now square \"3%2F2\" to get \"9%2F4\" (ie \"%283%2F2%29%5E2=%283%2F2%29%283%2F2%29=9%2F4\")
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\n" ); document.write( " \"y-2=1%28x%5E2%2B3x%2B9%2F4-9%2F4%29\" Now add and subtract this value inside the parenthesis. Doing both the addition and subtraction of \"9%2F4\" does not change the equation
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\n" ); document.write( " \"y-2=1%28%28x%2B3%2F2%29%5E2-9%2F4%29\" Now factor \"x%5E2%2B3x%2B9%2F4\" to get \"%28x%2B3%2F2%29%5E2\"
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\n" ); document.write( " \"y-2=1%28x%2B3%2F2%29%5E2-1%289%2F4%29\" Distribute
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\n" ); document.write( " \"y-2=1%28x%2B3%2F2%29%5E2-9%2F4\" Multiply
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\n" ); document.write( " \"y=1%28x%2B3%2F2%29%5E2-9%2F4%2B2\" Now add \"2\" to both sides to isolate y
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\n" ); document.write( " \"y=1%28x%2B3%2F2%29%5E2-1%2F4\" 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=1\", \"h=-3%2F2\", and \"k=-1%2F4\". 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=1x%5E2%2B3x%2B2\" we get:
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\n" ); document.write( " \"graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C1x%5E2%2B3x%2B2%29\" Graph of \"y=1x%5E2%2B3x%2B2\". Notice how the vertex is (\"-3%2F2\",\"-1%2F4\").
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\n" ); document.write( " Notice if we graph the final equation \"y=1%28x%2B3%2F2%29%5E2-1%2F4\" we get:
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\n" ); document.write( " \"graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C1%28x%2B3%2F2%29%5E2-1%2F4%29\" Graph of \"y=1%28x%2B3%2F2%29%5E2-1%2F4\". Notice how the vertex is also (\"-3%2F2\",\"-1%2F4\").
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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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