document.write( "Question 24062: I am learning basically how to graph quadratic equations. I dont really understand how to find the coordinates of the vertex. I also dont understand how to write an equation of the axis of symmetry. Can you please help me? \n" ); document.write( "
Algebra.Com's Answer #12773 by AnlytcPhil(1806)\"\" \"About 
You can put this solution on YOUR website!
I am learning basically how to graph quadratic equations. I dont really\r\n" );
document.write( "understand how to find the coordinates of the vertex. I also don't understand\r\n" );
document.write( "how to write an equation of the axis of symmetry. Can you please help me?\r\n" );
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document.write( "For the equation y or f(x) = a(x-h)2 + k\r\n" );
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document.write( "The vertex is this point:  (h, k)\r\n" );
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document.write( "The equation of the axis of symmetry is  this:  x = h\r\n" );
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document.write( "For the equation y or f(x) = ax2 + bx + c\r\n" );
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document.write( "The vertex is this point:  ( -b/(2a), c - b2/(4a)  )\r\n" );
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document.write( "The equation of the axis of symmetry is  this:  x = -b/(2a)\r\n" );
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document.write( "-------------------------------------------------------------\r\n" );
document.write( "Example 1:  y = -4(x+4)2-3\r\n" );
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document.write( "Compare to  y =  a(x-h)2+k\r\n" );
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document.write( "-h = +4, so h = -4\r\n" );
document.write( " k = -3.\r\n" );
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document.write( "The vertex is this point:  (h, k) = (-4,-3)\r\n" );
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document.write( "The equation of the axis of symmetry is  this:  x = h, or x = -4\r\n" );
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document.write( "==================================================================\r\n" );
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document.write( "Example 1: Find the vertex of f(x) = 2x2 - 12x + 19\r\n" );
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document.write( "                    Compare to f(x) = ax2 + bx + c\r\n" );
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document.write( "                                a = 2; b = -12; c = 19\r\n" );
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document.write( "The vertex is this point:  ( -b/(2a), c - b2/(4a)  ) =\r\n" );
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document.write( "( -(-12)/(2·2), 19 - (-12)2/(4·2)  )\r\n" );
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document.write( "      ( 12/4, 19 - 144/8  )  =\r\n" );
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document.write( "          ( 3, 19 - 18) =\r\n" );
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document.write( "               (3,1)\r\n" );
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document.write( "The equation of the axis of symmetry is  this: x = -b/(2a) \r\n" );
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document.write( "                                                x = -(-12)/(2·2)\r\n" );
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document.write( "                                                x = 3 \r\n" );
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document.write( "Edwin\r\n" );
document.write( "AnlytcPhil@aol.com
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