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1 vote
What are the solutions to the inequality (x-3)(x+5) <0?

o {X33X55)
o {X/-55X5-3)
o {x\-55x53)
{x-35x35)

User Aphenine
by
3.7k points

1 Answer

3 votes

You want a product to be negative. A product is negative if and only if the two factors have opposite signs.

So, there are two cases: either
x-3 is positive and
x+5 is negative, or vice versa. But since
x-3 is less than
x+5, the only possibility is that


\begin{cases}x-3<0\\x+5>0\end{cases} \iff \begin{cases}x<3\\x>-5\end{cases}

So, the solution is given by all numbers
x such that


-5<x<3

User Pathak Tejpal
by
3.5k points