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I need a maths guy-girl. Please. (A level y=mx+c stuff)

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    hey. thanks for clicking on this thread.

    anyway, i'm very confused. please help.

    how do I answer the following question: what is the equation of the line through the points (3,7) and (9,4)

    TSR are usually great with answering maths questions, it would be great to find an easy to understand solution on here.

    Thank you!
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    Find the gradient by getting the difference in y / the difference in x.From here using the equation y-y1 = m(x-x1) we can sub the gradient and a point on the line to get the equation of the line.
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    There are two components to figuring out the equation of a line: firstly, the gradient (which can be figured out using a simple formula), and the y-intercept (which can be figured out after we find the gradient)

    Your move..
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    (Original post by ETbuymilkandeggs)
    There are two components to figuring out the equation of a line: firstly, the gradient (which can be figured out using a simple formula), and the y-intercept (which can be figured out after we find the gradient)

    Your move..
    I'm confused.
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    (Original post by Alexion)
    I think you mean gcse y=mx+c stuff
    reported for being mean
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    (Original post by citibankrec)
    reported for being mean
    just stating a fact :emo:
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    once you have found an equation you should test it by putting in an x value & seeing if the y value which comes out is correct.
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    (Original post by ZiggyStarDust_)
    hey. thanks for clicking on this thread.

    anyway, i'm very confused. please help.

    how do I answer the following question: what is the equation of the line through the points (3,7) and (9,4)

    TSR are usually great with answering maths questions, it would be great to find an easy to understand solution on here.

    Thank you!
    Okie. Draw it out in a graph, and find the gradient. You can make it into a triangle to find the m (the gradient). So for every one that it goes across, how much it goes upwards. Then you can find the y-intercept which is c. I wont give you the answer or you wont learn, but any questions, gimmie a shout .

    I suck at teaching sorry. Just started a-level so kms
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    (Original post by ZiggyStarDust_)
    hey. thanks for clicking on this thread.

    anyway, i'm very confused. please help.

    how do I answer the following question: what is the equation of the line through the points (3,7) and (9,4)

    TSR are usually great with answering maths questions, it would be great to find an easy to understand solution on here.

    Thank you!
    Okay so let's get your gradient first. gradient equals y-y1 divided by x-x1.
    so take your y and x values:

    gradient = 7-4 divided by 3-9
    so 3/-6
    which can be simplified to 1/-2 or simply -1/2 or -0.5

    then substitute one of the points into the equation for a line.
    y-y1=m(x-x1) with m being your gradient. let's pick the point (3,7).

    y-7= -0.5(x-3).
    y-7= -0.5x - 1.5
    y= -0.5x + 5.5
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    (Original post by ZiggyStarDust_)
    I'm confused.
    I've explained it in quite a simple way. Perhaps flicking through a textbook would be more beneficial than going through examples - it's pointless if we're effectively teaching you new material.
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    (Original post by Emilia28)
    Okay so let's get your gradient first. gradient equals y-y1 divided by x-x1.
    so take your y and x values:

    gradient = 7-4 divided by 3-9
    so 3/-6
    which can be simplified to 1/-2 or simply -1/2 or -0.5

    then substitute one of the points into the equation for a line.
    y-y1=m(x-x1) with m being your gradient. let's pick the point (3,7).

    y-7= -0.5(x-3).
    y-7= -0.5x - 1.5
    y= -0.5x + 5.5
    THIS IS ALL I WANTED

    A STEP BY STEP ANSWER.

    thank you very, very much. Thank you.
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    (Original post by ZiggyStarDust_)
    THIS IS ALL I WANTED

    A STEP BY STEP ANSWER.

    thank you very, very much. Thank you.
    Not sure what the issue was, I gave you a step by step answer as the first answer here but you wanted someone to spoonfeed you the answer? Should've made it more obvious.
 
 
 
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