document.write( "Question 1124651: Find the quadratic equation function that has the given vertex and goes through the given point. Vertex(1,3), point (-2,0) f(x) = \n" ); document.write( "
Algebra.Com's Answer #740977 by rothauserc(4718)\"\" \"About 
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vertex form of quadratic equation is
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\n" ); document.write( "f(x) = a(x-h)^2 +k, where (h,k) is the vertex
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\n" ); document.write( "we are given the vertex (1,3)
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\n" ); document.write( "f(x) = a(x-1)^2 +3
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\n" ); document.write( "we are given point (-2,0) on the curve
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\n" ); document.write( "a(-2-1)^2 +3 = 0
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\n" ); document.write( "9a +3 = 0
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\n" ); document.write( "9a = -3
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\n" ); document.write( "a = -3/9 = -1/3
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\n" ); document.write( "f(x) = (-1/3)(x-1)^2 +3 =
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\n" ); document.write( "(-1/3)(x^2 -2x +1) +3 =
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\n" ); document.write( "-x^2/3 +2x/3 -1/3 + 3 =
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\n" ); document.write( "-x^2/3 +2x/3 +8/3
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\n" ); document.write( "f(x) = -x^2/3 +2x/3 +8/3
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