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How do i write this linear equation?

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x-intercept is -2. and goes through the point (1,1)

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  1. x - intercept is - 2 means  x= - 2 when y = 0

    that is  0 = -2m + c

            => c = 2m

    The line passes through (1,1)

    i.e 1 = m*1 + c

    => 1 = m + 2m

    => m = 1/3

    c= 2/3

    So equation is y = 1/3 x + 2/3


  2. Generally a linear equation is

                 y=mx +c

    For the x-intercept the value of y=0

                 0=-2m +c

    Using the point (1,1)

                 1=m +c

    These are simultaneous equations

                 -2m + c=0

                   m + c =1

                        -3m=-1

                            m=1/3

    Substituting m=1/3 into m + c =1 we get

                       c=2/3

    Linear equation now is y=1/3x +2/3

  3. Equation used: y=mx+c

    When x-intercept is -2 it basically means (-2,0)

    Now we have 2 points.

    To find m,

    (y1-y2)/(x1-x2)=(1-0)/(1-(-2))= 1/3

    To find c,

    Plug in either one of the given points into the equation.

    y=1/3*x+c

    Using point (1,1)

    1=1/3*1+c

    c=2/3

    Plug into the linear equation, you'll get:

    y = 1/3*x + 2/3

    or

    3y=x+2

      

  4. (-2,0) and (1,1) are both points. y=mx+b

    m = y(1)-y(2)/x(1)-x(2)

    =1-0/1-(-2)

    =1/3

    y=mx+b

    1=1/3(1)+b

    1-(1/3)=b

    2/3=b

    y=1/3x+2/3

    Another way to do it if you're allowed is to use the standard formula and go (y-y(0))=m(x-x(0)). But that's kind of cheating in this case. Haha.

  5. X intercept is such a point where y=0

    therefore the coordinate of x-intercept is    (-2,0)

    Now we will find the slope between two points

    m = (0-1)/(-2-1)

    m= 1/3

    Now assuming another point on the same line to be (x,y)

    and the other point to be (1,1)

    Being Linear equation the slope will remain same so

    1/3=(y-1)/x-1)

    solving it will result in

    y = x/3 + 2/3

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