document.write( "Question 398754: the vertex form equation of parabola identify coordinate v(h,k)
\n" ); document.write( "1)y=2x^2+32x+125
\n" ); document.write( "2)x^2-6x+y+9=0
\n" ); document.write( "

Algebra.Com's Answer #282489 by lwsshak3(11628)\"\" \"About 
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the vertex form equation of parabola identify coordinate v(h,k)
\n" ); document.write( "1)y=2x^2+32x+125
\n" ); document.write( "2)x^2-6x+y+9=0\r
\n" ); document.write( "\n" ); document.write( "To identify the coordinates of a parabola, you can write the equation in this form: y=(x-h)^2+k, (h,k) being the (x,y) coordinates of the vertex. You must complete the square to do this.\r
\n" ); document.write( "\n" ); document.write( "(1)y=2x^2+32x+125
\n" ); document.write( "completing the square
\n" ); document.write( "factor out 2
\n" ); document.write( "y=2(x^2+16x+64)+125-128 (we added 2*64 to complete the square,so we must add -128 to even things out
\n" ); document.write( "y=2(x+8)^2-3
\n" ); document.write( "vertex: (-8,-3)\r
\n" ); document.write( "\n" ); document.write( "(2)x^2-6x+y+9=0
\n" ); document.write( " y=-(x^2-6x+ )-9
\n" ); document.write( "y=-(x^2-6x+9)-9+9 (we added -9 to complete the square,so we must add 9 to even
\n" ); document.write( " things out
\n" ); document.write( "y=-(x-3)^2)+0
\n" ); document.write( "vertex: (3,0)\r
\n" ); document.write( "\n" ); document.write( "Another method for finding the coordinates of the vertex is to use the formula:
\n" ); document.write( "x=-b/2a,a being the coefficient of the x^2-term, and b the coefficient of the x-term. In equation (1) above, x=-16/2=-8, then substitute this value for x in the equation to find y=128-256+125=-3. If you are just trying to find the coordinates of the vertex, this might be a more simple way, but the first method will yield more information about the parabola.You should learn both ways.\r
\n" ); document.write( "\n" ); document.write( "see the following graphs of the two parabola equations:\r
\n" ); document.write( "\n" ); document.write( "\"+graph%28+300%2C+200%2C+-10%2C+5%2C+-6%2C+6%2C+2x%5E2%2B32x%2B125%2C-%28x%5E2-6x%2B9+%29%29\"\r
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