document.write( "Question 637355: In a quadratic equations why does the y value for subsequent x values increase or decrease in a pattern. For example, in the equation x^2 -2x -3, the y value when x is 1(vertex), 2, 3, and 4 is -4(vertex), -3, 0, and 5 respectively. Every time the y value is increasing by 1, then 3, then 5, then 7, then 9, and so on. Please explain this! \n" ); document.write( "
Algebra.Com's Answer #401579 by ewatrrr(24785)\"\" \"About 
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\n" ); document.write( "Hi,
\n" ); document.write( "y = x^2 -2x -3 | y = ax^2 + bx + c and \"-b%2F2a+=+2%2F%282%2A2%29+=+highlight%281%29\"
\n" ); document.write( "y =\"+%28x-highlight%281%29%29%5E2+-+1+-+3+\" |completing the Square to find Vertex form
\n" ); document.write( "y = (x-1)^2 - 4 , \"V%281%2C-4%29\"
\n" ); document.write( "\"y=a%28x-h%29%5E2+%2Bk\", the vertex form of a parabola, where(h,k) is the vertex
\n" ); document.write( "The pattern You are seeing is the result of the (x-1)^2 pattern
\n" ); document.write( "x (x-1)^2 y
\n" ); document.write( "1 0 -4
\n" ); document.write( "2 1 -3
\n" ); document.write( "3 4 0
\n" ); document.write( "4 9 5
\n" ); document.write( "5 16 12
\n" ); document.write( " \n" ); document.write( "
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