document.write( "Question 1084127: Complete the square to write each function in f(x) = a(x-h)^2 + k form. Determine the vertex and the axis of symmetry of the graph of the function. Then plot several points and complete the graph. \r
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Algebra.Com's Answer #698180 by Edwin McCravy(20056)\"\" \"About 
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document.write( "f(x) = -2x^2 +4x + 3\r\n" );
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document.write( "Factor out the coefficient of x² out of the first two terms\r\n" );
document.write( "on the right:\r\n" );
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document.write( "f(x) = -2(x² - 4x) + 3\r\n" );
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document.write( "1. To the side, multiply the coefficient of x inside the\r\n" );
document.write( "parentheses by 1/2.\r\n" );
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document.write( "       That's \"-2%2Aexpr%281%2F2%29\" or -1\r\n" );
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document.write( "2. Square the result of 1:\r\n" );
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document.write( "       That's \"%28-1%29%5E2\" or +1\r\n" );
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document.write( "3. Add, then subtract, that inside the parentheses\r\n" );
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document.write( "f(x) = -2(x² - 2x + 1 - 1) + 3\r\n" );
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document.write( "Factor the trinomial consisting of the first three terms\r\n" );
document.write( "inside the parentheses:\r\n" );
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document.write( "f(x) = -2((x-1)(x-1) - 1) + 3\r\n" );
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document.write( "Write (x-1)(x-1) as (x-1)²\r\n" );
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document.write( "f(x) = -2((x-1)² - 1) + 3\r\n" );
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document.write( "Remove the outer parentheses by distributing the -2 into \r\n" );
document.write( "the outer parentheses, leaving the (x-1)² intact:\r\n" );
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document.write( "f(x) = -2(x-1)² + 2 + 3\r\n" );
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document.write( "f(x) = -2(x-1)² + 5\r\n" );
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document.write( "So the vertex is (h,k) = (1,5)\r\n" );
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document.write( "Some points besides the vertex are found by substituting\r\n" );
document.write( "-2, -1, 0, 2, 3, 4 for x, getting:  \r\n" );
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document.write( "(-2,-13), (-1,3, (0,3), (2,3), (3,-3), (4,-13) \r\n" );
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document.write( "Axis of symmetry (in green), it is x = h or, in this case,\r\n" );
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document.write( "x = 1\r\n" );
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document.write( "Edwin
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