[tex]\bf y=-27(x+4)^3+1\implies 0=-27(x+4)^3+1
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-1=-27(x+4)^3\implies \cfrac{-1}{-27}=(x+4)^3\implies \cfrac{1}{27}=(x+4)^3
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\sqrt[3]{\cfrac{1}{27}}=x+4\implies \cfrac{\sqrt[3]{1}}{\sqrt[3]{27}}=x+4\implies \cfrac{1}{3}=x+4\implies \cfrac{1}{3}-4=x
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-\cfrac{11}{3}=x[/tex]