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Math Help - weird algebra problem

  1. #1
    Newbie Silverstaraptor's Avatar
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    Exclamation weird algebra problem

    Please help me! x-2y=3 How the heck do I graph this? heck, how the heck do I solve it?!
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    Quote Originally Posted by Silverstaraptor View Post
    Please help me! x-2y=3 How the heck do I graph this? heck, how the heck do I solve it?!
     x - 2y=3

    Add 2y to both sides

     x =3+2y

    subtract 3 from both sides:

     2y = x-3

    Divide both sides by 2:

     y = \frac{1}{2}x-\frac{3}{2}

    This is now in the form of a typical straight line... can you derive the gradient and y-intercept from here?

    Also, what do you mean by "solve" it? This is 1 equation in 2 unknowns, hence you cannot solve.
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  3. #3
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    Quote Originally Posted by Silverstaraptor View Post
    Please help me! x-2y=3 How the heck do I graph this? heck, how the heck do I solve it?!
    Because it does not involve anything more complicated than multiplying by a constant and subtracting, this is a "linear function": its graph is a straight line. And a straight line is determined by two points. Find any two x, y values that satisfy the equation, graph them and draw the line through them.
    One way to do that is to find the "intercepts". If y= 0 then x= 3 so (3, 0) is on the graph. If x= 0, then -2y= 3 or y= -3/2 so (0, -3/2) is on the graph. Draw the line between those two points.
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