<PRE><B>Question 455536</B>
f(x) = -3x^2+6x+c
I found that the vertex is (1,0) but I need to use the vertex to find c.
I tried subbing in the x value from the vertex, {{{-3(1)^2+6(1)+c}}} but that got me nowhere.
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You have it.
But that expression equals y; and y = 0 in the vertex.
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So, -3(1)^2+6(1)+c = 0
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-3 + 6 + c = 0
3 + c = 0
c = -3
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Cheers,
Stan H. 
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