How do you solve the inequality $18x-x^2<=81$ ?

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Answer 1 · 2016-11-17T12:25:46

The answer is $x inRR$

Let's rewrite the equation $18x-x^2<=81$

As, $x^2-18x+81>=0$

Factorising,

$(x-9)^2>=0$

The solution is $x inRR$

graph{x^2-18x+81 [-10, 10, -5, 5]}

How do you solve the inequality 18x-x^2<=8118x-x^2<=81?