document.write( "Question 84539: Write the equation of the axis of symmetry and find the coordinates of the vertex of the graph of each equation.\r
\n" ); document.write( "\n" ); document.write( "y=3xsqaured+4\r
\n" ); document.write( "\n" ); document.write( "y=3xsqaured+6x-17\r
\n" ); document.write( "\n" ); document.write( "y=3(x+1)sqaured-20\r
\n" ); document.write( "\n" ); document.write( "y=xsqaured+2x
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Algebra.Com's Answer #60889 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
1.
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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=3+x%5E2%2B0+x%2B4\" Start with the given equation
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\n" ); document.write( " \"y-4=3+x%5E2%2B0+x\" Subtract \"4\" from both sides
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\n" ); document.write( " \"y-4=3%28x%5E2%2B%280%29x%29\" Factor out the leading coefficient \"3\"
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\n" ); document.write( " Take half of the x coefficient \"0\" to get \"0\" (ie \"%281%2F2%29%280%29=0\").
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\n" ); document.write( " Now square \"0\" to get \"0\" (ie \"%280%29%5E2=%280%29%280%29=0\")
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\n" ); document.write( " \"y-4=3%28x%5E2%2B%280%29x%2B0-0%29\" Now add and subtract this value inside the parenthesis. Doing both the addition and subtraction of \"0\" does not change the equation
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\n" ); document.write( " \"y-4=3%28%28x%2B0%29%5E2-0%29\" Now factor \"x%5E2%2B%280%29x%2B0\" to get \"%28x%2B0%29%5E2\"
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\n" ); document.write( " \"y-4=3%28x%2B0%29%5E2-3%280%29\" Distribute
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\n" ); document.write( " \"y-4=3%28x%2B0%29%5E2-0\" Multiply
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\n" ); document.write( " \"y=3%28x%2B0%29%5E2-0%2B4\" Now add \"4\" to both sides to isolate y
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\n" ); document.write( " \"y=3%28x%2B0%29%5E2%2B4\" 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=3\", \"h=-0\", and \"k=4\". 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=3x%5E2%2B0x%2B4\" we get:
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\n" ); document.write( " \"graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C3x%5E2%2B0x%2B4%29\" Graph of \"y=3x%5E2%2B0x%2B4\". Notice how the vertex is (\"-0\",\"4\").
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\n" ); document.write( " Notice if we graph the final equation \"y=3%28x%2B0%29%5E2%2B4\" we get:
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\n" ); document.write( " \"graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C3%28x%2B0%29%5E2%2B4%29\" Graph of \"y=3%28x%2B0%29%5E2%2B4\". Notice how the vertex is also (\"-0\",\"4\").
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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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Solved by pluggable solver: Completing the Square to Get a Quadratic into Vertex Form

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\n" ); document.write( " \"y=3+x%5E2%2B6+x-17\" Start with the given equation
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\n" ); document.write( " \"y%2B17=3+x%5E2%2B6+x\" Add \"17\" to both sides
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\n" ); document.write( " \"y%2B17=3%28x%5E2%2B2x%29\" Factor out the leading coefficient \"3\"
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\n" ); document.write( " Take half of the x coefficient \"2\" to get \"1\" (ie \"%281%2F2%29%282%29=1\").
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\n" ); document.write( " Now square \"1\" to get \"1\" (ie \"%281%29%5E2=%281%29%281%29=1\")
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\n" ); document.write( " \"y%2B17=3%28x%5E2%2B2x%2B1-1%29\" Now add and subtract this value inside the parenthesis. Doing both the addition and subtraction of \"1\" does not change the equation
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\n" ); document.write( " \"y%2B17=3%28%28x%2B1%29%5E2-1%29\" Now factor \"x%5E2%2B2x%2B1\" to get \"%28x%2B1%29%5E2\"
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\n" ); document.write( " \"y%2B17=3%28x%2B1%29%5E2-3%281%29\" Distribute
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\n" ); document.write( " \"y%2B17=3%28x%2B1%29%5E2-3\" Multiply
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\n" ); document.write( " \"y=3%28x%2B1%29%5E2-3-17\" Now add \"%2B17\" to both sides to isolate y
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\n" ); document.write( " \"y=3%28x%2B1%29%5E2-20\" 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=3\", \"h=-1\", and \"k=-20\". Remember (h,k) is the vertex and \"a\" is the stretch/compression factor.
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\n" ); document.write( " Notice if we graph the original equation \"y=3x%5E2%2B6x-17\" we get:
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\n" ); document.write( " \"graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C3x%5E2%2B6x-17%29\" Graph of \"y=3x%5E2%2B6x-17\". Notice how the vertex is (\"-1\",\"-20\").
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\n" ); document.write( " Notice if we graph the final equation \"y=3%28x%2B1%29%5E2-20\" we get:
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\n" ); document.write( " \"graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C3%28x%2B1%29%5E2-20%29\" Graph of \"y=3%28x%2B1%29%5E2-20\". Notice how the vertex is also (\"-1\",\"-20\").
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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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\n" ); document.write( "Since the equation \"y=3%28x%2B1%29%5E2-20\" is already in vertex form, the equation of the axis of symmetry is \"x=-1\" and the vertex is (-1,-20). Remember, any equation in vertex form \"y=a%28x-h%29%5E2%2Bk\" has an axis of symmetry of \"x=h\" and a vertex of (h,k)\r
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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%2B2+x%2B0\" Start with the given equation
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\n" ); document.write( " \"y-0=1+x%5E2%2B2+x\" Subtract \"0\" from both sides
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\n" ); document.write( " \"y-0=1%28x%5E2%2B2x%29\" Factor out the leading coefficient \"1\"
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\n" ); document.write( "
\n" ); document.write( " Take half of the x coefficient \"2\" to get \"1\" (ie \"%281%2F2%29%282%29=1\").
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\n" ); document.write( " Now square \"1\" to get \"1\" (ie \"%281%29%5E2=%281%29%281%29=1\")
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\n" ); document.write( " \"y-0=1%28x%5E2%2B2x%2B1-1%29\" Now add and subtract this value inside the parenthesis. Doing both the addition and subtraction of \"1\" does not change the equation
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\n" ); document.write( " \"y-0=1%28%28x%2B1%29%5E2-1%29\" Now factor \"x%5E2%2B2x%2B1\" to get \"%28x%2B1%29%5E2\"
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\n" ); document.write( " \"y-0=1%28x%2B1%29%5E2-1%281%29\" Distribute
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\n" ); document.write( " \"y-0=1%28x%2B1%29%5E2-1\" Multiply
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\n" ); document.write( " \"y=1%28x%2B1%29%5E2-1%2B0\" Now add \"0\" to both sides to isolate y
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\n" ); document.write( " \"y=1%28x%2B1%29%5E2-1\" 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=-1\", and \"k=-1\". Remember (h,k) is the vertex and \"a\" is the stretch/compression factor.
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\n" ); document.write( " Notice if we graph the original equation \"y=1x%5E2%2B2x%2B0\" we get:
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\n" ); document.write( " \"graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C1x%5E2%2B2x%2B0%29\" Graph of \"y=1x%5E2%2B2x%2B0\". Notice how the vertex is (\"-1\",\"-1\").
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\n" ); document.write( " Notice if we graph the final equation \"y=1%28x%2B1%29%5E2-1\" we get:
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\n" ); document.write( " \"graph%28500%2C500%2C-10%2C10%2C-10%2C10%2C1%28x%2B1%29%5E2-1%29\" Graph of \"y=1%28x%2B1%29%5E2-1\". Notice how the vertex is also (\"-1\",\"-1\").
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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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