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C1 - Why are you able to multiply a coordinate geometry equation like this? Watch

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    I have the equation: y-1 = 5/3 (x-3), and the question wants it in the form ax+by+c=0. I know that I am able to multiply each term by 3 in order to get it all as whole numbers, but how is that the same equation?

    Surely multiplying everything by 3 would mean the equation is now different, as each term is now 3 times larger. Can you explain this to me please?

    Thanks
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    (Original post by blobbybill)
    I have the equation: y-1 = 5/3 (x-3), and the question wants it in the form ax+by+c=0. I know that I am able to multiply each term by 3 in order to get it all as whole numbers, but how is that the same equation?

    Surely multiplying everything by 3 would mean the equation is now different, as each term is now 3 times larger. Can you explain this to me please?

    Thanks
    You have to multiply both sides of the equation by 3. If you only multiply the right then it won't be the same equation as you say. But if you do it to both sides then the equation remains the same.
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    (Original post by blobbybill)
    I have the equation: y-1 = 5/3 (x-3), and the question wants it in the form ax+by+c=0. I know that I am able to multiply each term by 3 in order to get it all as whole numbers, but how is that the same equation?

    Surely multiplying everything by 3 would mean the equation is now different, as each term is now 3 times larger. Can you explain this to me please?

    Thanks
    It would still be the same equation.

    y=\frac{x}{2} and 2y=x are equivalent just in different forms. You can easily verify this yourself by drawing an x and y column table for each of the above and fill them out - they would be the same. (or sketch them)

    When you multiply/divide both sides of an equation by a number, the quantities on both sides are preserved and remain equal, hence no change.
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    You just went full retard bro, never go full retard haha jk

    You're only halfway through! Put the equation into the y=mx+c form and then from there move all values on one said to the other for it to look like ax+by+c=0


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