document.write( "Question 1196808: Sketch the following functions by first solving for the x intercepts using the quadratic formula.  If there are no x intercepts then use the method explained in class...this makes use of the fact that raising or lowering a parabola by some amount does not change the x coordinate of the vertex.  So...remove the constant from the right side, factor what's left to determine x intercepts.  The average of those is the x coordinate of the vertex.  Then substitute that back into the original equation to solve for the y coordinate of the vertex. 
\n" ); document.write( "y = 3x^2+15x+30   AND   y = -x^2+4x-8
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Algebra.Com's Answer #829811 by josgarithmetic(39617)\"\" \"About 
You can put this solution on YOUR website!
This is not the full solution.\r
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\n" ); document.write( "\n" ); document.write( "\"3%28x%5E2%2B5x%2B10%2B%285%2F2%29%5E2-%285%2F2%29%5E2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"3%28x%5E2%2B5x%2B%285%2F2%29%5E2%2B10-%285%2F2%29%5E2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"3%28%28x%2B5%2F2%29%5E2%2B40%2F4-25%2F4%29\"
\n" ); document.write( "\"3%28%28x%2B5%2F2%29%5E2%2B15%2F4%29\"\r
\n" ); document.write( "\n" ); document.write( "\"3%28x%2B5%2F2%29%5E2%2B45%2F4\"
\n" ); document.write( "\"y=3%28x%2B5%2F2%29%5E2%2B11%261%2F4\"-----------you can read the vertex and solve for the roots.\r
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\n" ); document.write( "\n" ); document.write( "\"-%28x%5E2-4x%2B8%29\"
\n" ); document.write( "\"-%28x%5E2-4x%2B4-4%2B8%29\"
\n" ); document.write( "\"-%28%28x-2%29%5E2%2B4%29\"
\n" ); document.write( "\"y=-%28x-2%29%5E2-4\"--------------you can read the vertex and solve for the roots.
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