Question 443092
We know that
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0 = a + b +c
-4 = 0 + 0 + c
6 = 4a + 2b +c
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we know c = -4
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0 = a+b-4
6 = 4a +2b -4
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a + b = 4
4a + 2b = 10

*[invoke linear_substitution "a", "b", 1, 1, 4, 4, 2, 10 ]

So a = 1 b = 3 c =-4

So our quadratic is x^2 + 3x - 4