document.write( "Question 316858: Write the quadratic function in the form y = a(x - h)2 + k. Find the veertex, axis of symmetry, domain and range
\n" ); document.write( "y = -2x2 - 8x - 5
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Algebra.Com's Answer #226818 by solver91311(24713)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "Factor out -2 from the variable terms:\r
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\n" ); document.write( "\n" ); document.write( "Divide the coefficient on the term by 2 and square the result. \r
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\n" ); document.write( "\n" ); document.write( "Add 4 inside the parentheses and outside the parentheses\r
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\n" ); document.write( "\n" ); document.write( "Factor the perfect square in the parentheses:\r
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\n" ); document.write( "\n" ); document.write( "Domain: (All real numbers, just like any other polynomial function) \r
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\n" ); document.write( "\n" ); document.write( "Range: The lead coefficient is negative, therefore the parabola opens downward and the vertex represents a maximum value of the function. That maximum value is the -coordinate of the vertex, namely . The range is unconstrained less than the maximum, so Range: \r
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\n" ); document.write( "\n" ); document.write( "You didn't ask for the intercepts, but here they are anyway:\r
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\n" ); document.write( "\n" ); document.write( "The -intercept is at the value of the function when , so:\r
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\n" ); document.write( "\n" ); document.write( "and the -intercept is \r
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\n" ); document.write( "\n" ); document.write( "The -intercepts are the roots of:\r
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\n" ); document.write( "\n" ); document.write( "Verification of that last step is left as an exercise for the student.\r
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\n" ); document.write( "\n" ); document.write( "Hence the -intercepts are and \r
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