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Math Help - Inverse Problems Functions

  1. #1
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    Inverse Problems Functions




    Explain best you can and if possible please just give answers i have to go to sleep dont know if i can finish in morning
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  2. #2
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    A linear equation has the form y=mx+c.

    In the first set you are given m. Substitute the points and then rearrange to find c. So for the first question,
    y = -2x+c and (x,y) = (2,1)
    1 = -2(2)+c
    1=-4+c
    1+4 =c
    c=5.
    y = -2x+5

    In the second set you are given 2 points. Call them (x_1,y_1) and (x_2, y_2), and use the formula m = \frac{y_2-y_1}{x_2-x_1}, then use the method for the first set.
    The first question looks like this:
    (x_1,y_1) = (2,3) and (x_2,y_2) = (5,9)
    m = \frac{9-3}{5-2}
    =\frac{6}{3}
    =2

    y = 2x+c
    3=2(2)+c
    3=4+c
    3-4 = c
    c=-1
    y=2x-1
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  3. #3
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    Quote Originally Posted by HamzaH View Post



    Explain best you can and if possible please just give answers i have to go to sleep dont know if i can finish in morning
    This is not a site for doing your homework.

    Option 1: Use the model y - y_1 = m (x - x_1).

    For m = 3 and (-1, -10): y - (-10) = 3 (x - (-1)) \Rightarrow y = 3x - 7.

    Option 2: Use the model y = mx + c.

    For m = 3 and (-1, -10): y = 3x + c. Substitute (-1, -10) and solve for c: -10 = -3 + c => c = -7.


    Note that f(5) = -1 etc. means that the point (5, -1) lies on the line.
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