document.write( "Question 855009: ok so I got a question today in math foundations 20... I have to sketch a graph of a quadratic equation but I don't have a equation he gave me just information. I only know the axis of symmetry, x=3 the vertex is (3,5) and finally the y-intercept = (0,8) I only got that no equation how to I graph that? and what would the equation be? \n" ); document.write( "
Algebra.Com's Answer #515022 by josgarithmetic(39617)\"\" \"About 
You can put this solution on YOUR website!
Understand the standard form for a quadratic (or at least a parabolic) equation.
\n" ); document.write( "\"y=a%28x-h%29%5E2%2Bk\";
\n" ); document.write( "vertex is (h,k), and this occurs on the symmetry axis (for a parabola).
\n" ); document.write( "The factor, a, is information about stretching or shrinking, in this form, vertically. The form shown has a vertical symmetry axis. \r
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\n" ); document.write( "\n" ); document.write( "According to what you are given, you can use that data to fill the standard form equation. If symmetry axis is x=3, then the parabola opens either upward or downward and the vertex is on this axis.
\n" ); document.write( "\"y=a%28x-3%29%5E2%2B5\"
\n" ); document.write( "and use the given y-intercept to help find a.
\n" ); document.write( "-
\n" ); document.write( "First, solve for a.
\n" ); document.write( "\"a%28x-3%29%5E2=y-5\"
\n" ); document.write( "\"a=%28y-5%29%2F%28x-3%29%5E2\"
\n" ); document.write( "Substitute with (0,8).
\n" ); document.write( "\"a=%288-5%29%2F%280-3%29%5E2\"
\n" ); document.write( "\"a=3%2F%289%29\"
\n" ); document.write( "\"a=1%2F3\"
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\n" ); document.write( "EQUATION: \"highlight%28y=%281%2F3%29%2A%28x-3%29%5E2%2B5%29\"
\n" ); document.write( "The parabola is vertical, has a minimum, vertex of (3,5); the coefficient on the leading term came from knowing the y intercept.\r
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\n" ); document.write( "\n" ); document.write( "\"graph%28300%2C300%2C-5%2C15%2C-5%2C15%2C%281%2F3%29%28x-3%29%5E2%2B5%29\"
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