Mathematics
mladams101
6

can yu help me with this question? n2- n - 20= 0

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(1) Answers
lyssie11234

[latex]n^2-n-20=0\\\\a=1;\ b=-1;\ c=-20\\\\\Delta=b^2-4ac\\\\\Delta=(-1)^2-4\cdot1\cdot(-20)=1+80=81\\\\n_1=\frac{-b-\sqrt\Delta}{2a}\ and\ n_2=\frac{-b+\sqrt\Delta}{2a}\\\\\sqrt\Delta=\sqrt{81}=9\\\\n_1=\frac{1-9}{2\cdot1}=\frac{-8}{2}=-4;\ n_2=\frac{1+9}{2\cdot1}=\frac{10}{2}=5\\\\Answer:n=-4\ or\ n=5.[/latex]

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