Donnialy
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x² + 6x + 8 < 0 pls help the online methods are so hard

tysm ppl
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username5490332
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first step would be to factorise..
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Muttley79
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(Original post by Donnialy)
x² + 6x + 8 < 0 pls help the online methods are so hard

tysm ppl
How far have you got?

A good start would be to consider x² + 6x + 8 = 0
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Donnialy
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Hey guys so i tried to factorise and got

(x+2)(x+4) <0
x <-2, x < -4

How would I plot this on a graph or inequality line?

EG of equality line

_____________________
1 2 3 4 5 6 7 8 9 10

Sorry if this doesn't make sense
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Muttley79
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(Original post by Donnialy)
Hey guys so i tried to factorise and got

(x+2)(x+4) <0
x <-2, x < -4

How would I plot this on a graph or inequality line?

EG of equality line

_____________________
1 2 3 4 5 6 7 8 9 10

Sorry if this doesn't make sense
That's not the way I'd tackle it.
consider x² + 6x + 8 = 0
(x + 2)( x + 4) = 0

x = -2 or -4

Sketch the curv and we want the x values which give the curve below the x-axis -4 < x < -2 not sure where you got your inequalities ...

Do you know how to show this on the number line?
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themagicturtle
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(Original post by Donnialy)
Hey guys so i tried to factorise and got

(x+2)(x+4) <0
x <-2, x < -4

How would I plot this on a graph or inequality line?

EG of equality line

_____________________
1 2 3 4 5 6 7 8 9 10

Sorry if this doesn't make sense
You've made an error here (but not in the factorising). Try drawing a graph of the equation (ie draw y = x^2 + 6x + 8) - you're looking for any areas where y < 0 (since the quadratic is less than 0).

For the question about the numberline:
Image

Hopefully the above image might help you a bit. But try the graph trick first and see where that lands you.
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Donnialy
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(Original post by Muttley79)
That's not the way I'd tackle it.
consider x² + 6x + 8 = 0
(x + 2)( x + 4) = 0

x = -2 or -4

Sketch the curv and we want the x values which give the curve below the x-axis -4 < x < -2 not sure where you got your inequalities ...

Do you know how to show this on the number line?
wait so all i have to do is draw the graph and look for a number for x which is between -2 and -3 ?!? ahh I can do that! tysm for helping
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Donnialy
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(Original post by themagicturtle)
You've made an error here (but not in the factorising). Try drawing a graph of the equation (ie draw y = x^2 + 6x + 8) - you're looking for any areas where y < 0 (since the quadratic is less than 0).

For the question about the numberline:
Image

Hopefully the above image might help you a bit. But try the graph trick first and see where that lands you.
tysm for replying, i think that image will rlly help someone else said about the graph too, imma try that.
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Muttley79
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(Original post by Donnialy)
tysm for replying, i think that image will rlly help someone else said about the graph too, imma try that.
You need the graph to find the inequalities then use the number line with open circles on the -4 and -2 and a line joining them.
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Donnialy
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(Original post by Muttley79)
You need the graph to find the inequalities then use the number line with open circles on the -4 and -2 and a line joining them.
i think i got it ! tysm everyone for helping
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