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Can you simplyify both sides of the equal sign when working out intersection points? Watch

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    Would multiplying and dividing both side of an equation when working out intersection point of 2 curves change the points of intersection?
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    Never divide - factorise
    Make sure you don't add solutions when you multiply
    Other than that it's ok
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    Also if it's by a constant it's ok.
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    (Original post by TheAdviser101)
    Would multiplying and dividing both side of an equation when working out intersection point of 2 curves change the points of intersection?
    Do you have an example? Though as above, never divide by variables, factor them out instead.
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    (Original post by RDKGames)
    Do you have an example? Though as above, never divide by variables, factor them out instead.
    9x^2 + 6x + 12 = 3x - 6

    So in this case if divide both graphs by 3 (take out a factor of 3), the points of intersection will be identical as the original? btw what do you mean by dividing by variables? Can you give an example. Thanks
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    (Original post by TheAdviser101)
    9x^2 + 6x + 12 = 3x - 6

    So in this case if divide both graphs by 3 (take out a factor of 3), the points of intersection will be identical as the original? btw what do you mean by dividing by variables? Can you give an example. Thanks
    Dividing and taking out a factor is not the same thing. Since 3 is a constant non-zero term you can freely divide by it and the quantity's will still remain equal, so yes the answer's will be the same.

    Dividing by variables would be something like dividing both sides by x like so: x^2=2x \Rightarrow x=2 (as x varies - hence a variable) which is wrong as you are losing a solution.
 
 
 
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