document.write( "Question 328737: Find the vertex, the line of symmetry, the maximum or minimum value of the quadratic function, and graph the function on paper. f(x)=x^2-4x-4 \n" ); document.write( "

Algebra.Com's Answer #235558 by Fombitz(32388) $\"\"$ $\"About$

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Complete the square to put into vertex form, $\"y=a%28x-h%29%5E2%2Bk\"$ where (h,k) is the vertex.
\n" ); document.write( " $\"f%28x%29=%28x%5E2-4x%29-4\"$
\n" ); document.write( " $\"f%28x%29=%28x%5E2-4x%2B4%29-4-4\"$
\n" ); document.write( " $\"f%28x%29=%28x-2%29%5E2-8\"$
\n" ); document.write( "Comparing, the vertex is (2,-8).
\n" ); document.write( "THe vertex lies on the line of symmetry, $\"x=2\"$ .
\n" ); document.write( "The parabola opens upwards since the coefficient of the $\"x%5E2\"$ term is positive so the function value at the vertex is a minimum.
\n" ); document.write( " $\"ymin=-8\"$
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\n" ); document.write( "Verify by graphing,
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