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0=30-4x+0.4x^2
We move all terms to the left:
0-(30-4x+0.4x^2)=0
We add all the numbers together, and all the variables
-(30-4x+0.4x^2)=0
We get rid of parentheses
-0.4x^2+4x-30=0
a = -0.4; b = 4; c = -30;
Δ = b2-4ac
Δ = 42-4·(-0.4)·(-30)
Δ = -32
Delta is less than zero, so there is no solution for the equation
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