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End of an quadratic inequality

I was doing some C1 revision, so I did a past paper. I did an inequality question and I factorised it well, but the problem was the last part.

The question was: x(3x-13)>=10

I factorised it to:

(3x+2)(x-5)>0

But I don't know whether it's -2/3<x<5 or x<-2/3 and x>5, the latter is the answer, but I don't know how they got it. The mark scheme says "chose outside region". Can someone please explain how to end this solving?
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Pangol
15
Draw a graph of y = (3x+2)(x-5) - I assume that this will be easy for you.

You want to know where (3x+2)(x-5) > 0. This is the same as finding the values of x where y > 0. You should be able to easily read these from your graph.
ok so assume the inequality sign is equal, we get x-5=0 make the x alone, so add 5, x=5

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