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Help please on Quadratic Inequalities watch

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    Use set notation to describe the set of values of x for which:
    X^2-x-6>0. And 10-2x<5
    (X+2)(x-3)>0
    (X+2)(x-3)=0
    X=-2 and x=3
    X<3
    X>-2

    10-2x<5
    -2x<5-10
    X>-5/-2

    Answer is (x:x >3)
    Please show me how....😀
    Thanks for your helpxxx
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    (Original post by Musicanor)
    Use set notation to describe the set of values of x for which:
    X^2-x-6>0. And 10-2x<5
    (X+2)(x-3)>0
    (X+2)(x-3)=0
    X=-2 and x=3
    X<3
    X>-2

    10-2x<5
    -2x<5-10
    X>-5/-2

    Answer is (x:x >3)
    Please show me how....😀
    Thanks for your helpxxx
    For questions like these, it's best to sketch a quick graph of what you've been given. You would first draw the graph of y=X^2-x-6. You have correctly calculated the critical values, being -2 and 3, so we know where this graph would cross the x axis. Now, we're looking for regions where the graph y=X^2-x-6 is greater than zero. From or sketch, we can see that this occurs when x>3 or x<-2. This is why it's best to draw a sketch, as it gives you a visual aid to help you with the question.I hope this helped
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    (Original post by HotDetermination)
    For questions like these, it's best to sketch a quick graph of what you've been given. You would first draw the graph of y=X^2-x-6. You have correctly calculated the critical values, being -2 and 3, so we know where this graph would cross the x axis. Now, we're looking for regions where the graph y=X^2-x-6 is greater than zero. From or sketch, we can see that this occurs when x>3 or x<-2. This is why it's best to draw a sketch, as it gives you a visual aid to help you with the question.I hope this helped
    X thanks
 
 
 
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