SOLUTION: Determine the quadratic function f whose vertex is (2,-7) and y intercept is -3

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Question 1096280: Determine the quadratic function f whose vertex is (2,-7) and y intercept is -3
Answer by sandeepvijay(8) About Me  (Show Source):
You can put this solution on YOUR website!
Let the quadratic function be y+=+x%5E2%2B%28b%2Fa%29x%2B%28c%2Fa%29

Since y-intercept is -3, therefore y = -3 for x = 0. Therefore,
-3+=+0%5E2+%2B+%28b%2Fa%29%2A0+%2B+%28c%2Fa%29 => c%2Fa+=+-3
Since (2,-7) is on the quadratic function (as this is the vertex), for x= 2, y must be equal to -7
-7+=+2%5E2%2B2%28b%2Fa%29-3 => b%2Fa+=+-4
Therefore, the function is y+=+x%5E2+-4x+-3