SOLUTION: If we express 3x^2 + x - 4 in the form a(x - h)^2 + k, then what is k?

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Question 1086042: If we express 3x^2 + x - 4 in the form a(x - h)^2 + k, then what is k?
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

3x%5E2+%2B+x+-+4 in the form a%28x+-+h%29%5E2+%2B+k,
%283x%5E2+%2B+x%29+-+4
3%28x%5E2+%2B+%281%2F3%29x%2Bh%5E2%29-3h%5E2+-+4
3%28x%5E2+%2B+%281%2F3%29x%2Bh%5E2%29-3h%5E2+-+4
since coefficient of x%5E2 is a=1 and 2ah=1%2F3-> 2h=1%2F3->h=1%2F6 and we have
3%28x%5E2+%2B+%281%2F3%29x%2B%281%2F6%29%5E2%29-3%281%2F6%29%5E2+-+4
3%28x%2B1%2F6%29%5E2-3%281%2F36%29+-+4
3%28x%2B1%2F6%29%5E2-cross%283%29%281%2Fcross%2836%2912%29+-+4
3%28x%2B1%2F6%29%5E2-1%2F12+-+48%2F12
3%28x%2B1%2F6%29%5E2+-+49%2F12

then k=-+49%2F12