document.write( "Question 752747: Hi, I'm having trouble figuring out a parabola's equation. The Y intercept is (0,6), the vertex is (2,8). These are the only points given. Can you please explain to me how to work out the equation/what it is?\r
\n" ); document.write( "\n" ); document.write( "Thanks a lot,
\n" ); document.write( "Nathan \n" ); document.write( "
Algebra.Com's Answer #457996 by rothauserc(4718)\"\" \"About 
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Find the equation of the parabola with Y intercept (0,6) and the vertex is (2,8). These are the only points given. \r
\n" ); document.write( "\n" ); document.write( "The vertex form of a quadratic function is
\n" ); document.write( "y=a(x−h)^2 + k
\n" ); document.write( "where (h,k) is the vertex. Use your given vertex, and solve for a using the fact that you know the y-intercept.\r
\n" ); document.write( "\n" ); document.write( "Note that the vertex and any other point on the curve would be sufficient.\r
\n" ); document.write( "\n" ); document.write( "y = a(x-2)^2 + 8\r
\n" ); document.write( "\n" ); document.write( "6 = a(0-2)^2 + 8
\n" ); document.write( "6 = 4a + 8
\n" ); document.write( "4a = -2
\n" ); document.write( "a = -1/2\r
\n" ); document.write( "\n" ); document.write( "y = (-1/2)(x-2)^2 + 8\r
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