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Question:

duckey
duckey
Student
High School - 9th Grade

ok I dont get what to do for slope intercept Y=mx+b

Y=2x+4

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Posted by duckey on Monday November 9, 2009 at 1:24 PM and tagged with math, slope intercept.

Answers:


  1. chikazu Student
    Community / Jr. College

    Y is equal to mx+b, with m being the slope and b being the spot on the Y axis that the line intercepts at. So, for Y=2x+4, it would have a slope of 2/1, the line would intercept at 4, and it would go to the right. Does that help?

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    Posted by chikazu on Monday November 9, 2009 at 1:50 PM

  2. neela
    neela Teacher
    Graduate School

    eNotes Editor

    y=mx+b is the slope intercept form of a straight line.

    When x=0,  y= m*0+b=b. Therefore, (0,b) which is a point on y axis  and it intercepts y axis at a distance b from the origin.

    Now Let us plug y=0 in the equation, 0=m+b. So, x = -b/m. So,

    In the triangle ABC, A = (-b/m,0),  O, the origin =(0,0) and C= (0,b), the slope of the line y=mx+b is given by:

    slope = tan angleOAC = OC/AO= (b-0)/[0-(-b/m)]= b/(b/m)=m.

    Therefore, m is the slope and and b is the intercept of the line y = mx+b. Or  y = slope times x + y intercept.

    Similarly, for a given line, y=x+10 or y = 1*x+10, 1 is the slope and 10 is the intercept on y axis.

    Similarly y=2x+4 is  a line whose slope is 2 and the line cuts y axis at (0,4) or the y intercept of this line is 4.

     

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    Posted by neela on Monday November 9, 2009 at 4:52 PM

  3. subbundd
    subbundd Teacher
    High School - 12th Grade

    Slope intercept form is x/a+y/b=1 where a ix intercept on x- axis and  b is intercept on y -axis.slope m= TanA =b/a

    The givem Eqis Y=2x+4 or 2x-y=-4 Divide both sides by -4 We get

    x/(-2)+y/(-4)=1

    Therefore a=-2 and b= -4.and slope = b/a = 2.

    Since both intercepts are negative the graph lies in IIIrd the Quadrant.

     

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    Posted by subbundd on Tuesday November 10, 2009 at 6:48 AM