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the question is Solve the following inequality

X^2 -7x +12<0

if you factorise it you get (x-3)(x-4)
2. You could take numbers either side of those numbers and put it into the x^2-7x+12 and see if it comes out as above or below zero, numbers plus/minus 0.1 from the answers you found above,

x = 3.1 y=-0.09
x = 2.9 y= 0.11

x= 4.1 y=0.11
x= 3.9 y = -0.09
3. (Original post by Meat Loaf Rocks)

the question is Solve the following inequality

X^2 -7x +12<0

if you factorise it you get (x-3)(x-4)
(x-3)(x-4)<0
One of the brackets has to be negative at the same time as the other is positive.
(x-3) can't be negative while (x-4) is positive.
Hence (x-4) is negative and (x-3) is positive.
so: 3<x<4.
4. cheers great help
5. The way I do it is by sketching the graph, for easier examples anyway like quadratics. It will be below the x axis when x<0, so you can see that it must be between 3 and 4, but not including 3 and 4 because at those points y=0, so it isn't <0.

x > 3 and x < 4 so

3 < x < 4

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