document.write( "Question 1033705: The function f(x)=x^2-9x+14 has a maximum or minimum value? What is the value? \n" ); document.write( "
Algebra.Com's Answer #648381 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
\"+f%28x%29+=+x%5E2+-+9x+%2B+14+\"
\n" ); document.write( "The vertex ( either maximum or minimum )
\n" ); document.write( "is at \"+x%5Bv%5D+=+-b%2F%282a%29+\" when the form is:
\n" ); document.write( "\"+a%2Ax%5E2+%2B+b%2Ax+%2B+c+\"
\n" ); document.write( "\"+a+=+1+\"
\n" ); document.write( "\"+b+=+-9+\"
\n" ); document.write( "\"+x%5Bv%5D+=+-%28-9%29+%2F+%28+2%2A1+%29+\"
\n" ); document.write( "\"+x%5Bv%5D+=+9%2F2+\"
\n" ); document.write( "------------------------
\n" ); document.write( "Another way to see this is: the vertex is midway
\n" ); document.write( "between the roots
\n" ); document.write( "\"+f%28x%29+=+0+\"
\n" ); document.write( "\"+f%28x%29+=+%28+x-7+%29%2A%28+x-2+%29+\"
\n" ); document.write( "\"+x+=+7+\"
\n" ); document.write( "\"+x+=+2+\"
\n" ); document.write( "-------------
\n" ); document.write( "The midway point is at:
\n" ); document.write( "\"+x%5Bv%5D+=+%28+7+%2B+2+%29+%2F+2+\"
\n" ); document.write( "\"+x%5Bv%5D+=+9%2F2+\"
\n" ); document.write( "---------------------
\n" ); document.write( "Plug this value back into equation
\n" ); document.write( "\"+f%289%2F2%29+=+%289%2F2%29%5E2+-+9%2A%289%2F2%29+%2B+14+\"
\n" ); document.write( "\"+f%289%2F2%29+=+81%2F4+-+81%2F2+%2B+14+\"
\n" ); document.write( "\"+f%289%2F2%29+=+81%2F4+-+162%2F4+%2B+56%2F4+\"
\n" ); document.write( "\"+f%289%2F2%29+=+-25%2F4+\"
\n" ); document.write( "-------------------
\n" ); document.write( "The vertex is at ( 9/2, -25/4 ), which means it must be
\n" ); document.write( "a minimum since there are 2 roots on either side which
\n" ); document.write( "are above the vertex.
\n" ); document.write( "--------------------
\n" ); document.write( "Here's the plot:
\n" ); document.write( "\"+graph%28+400%2C+400%2C+-2%2C+10%2C+-8%2C+10%2C+x%5E2+-+9x+%2B+14++%29+\"
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