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-x^2+6x-16=0
We add all the numbers together, and all the variables
-1x^2+6x-16=0
a = -1; b = 6; c = -16;
Δ = b2-4ac
Δ = 62-4·(-1)·(-16)
Δ = -28
Delta is less than zero, so there is no solution for the equation
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