Tuesday, February 24, 2009

The y-intercept

What is the y-intercept?
What really does the y-intercept mean?

From the general equation of a straight line, the y-intercept is c.
Why is this true?

What is the y-intercept's of the following
  1. y = 6x + 3
  2. y = -12x + 5
  3. y = 2x - 6
  4. 2y = 5x + 3
  5. 3y = - 4x + 1
  6. 2y + x = 7
  7. 3y + 5x = 11
  8. 2y - 4x = 7
  9. 4y + 3x + 2 = 0
  10. 2y -3x + 5 = 0

16 comments:

  1. the why intercept is the height of the vector

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  2. the y intercept is the point where the line cuts the x axis.

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  3. Or is it when the line cuts the y axis

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  4. I am sure now that the y intercept is the point where the line crosses the y axis when x is zero

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  5. In coordinate geometry the y intercept is the y value of the point where the graph of a function or relation intercepts the y axis of the coordinate system.

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  6. In other words i must put this in simple words so the meaning can stand out from the definition and my siplicity of the meaning will be understood.

    the Y INTERCEPT of a function is the Y VALUE of a point at which it INTERCEPTS the line x=0(THE Y AXIS).

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  7. In the general equation of a straight line the y intercept is c because when x=0 y=c

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  8. 1)y intercept is 3
    2)y intercept is 5
    3)y intercept is -6
    4)y intercept is 3
    5)y intercept is 1

    7)y intercept is 5

    9)y intercept is 3
    10)y intercept is -3

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  9. The y-intercept is when x=0, y=c.
    Given the formula y=mx+c
    y=a coordinate on the y-axis.
    x=a coordinate on the x-axis.
    m=gradient or a linear change on the x and y axis. Note:the formula y=mx+c only applies to straight lines and can be found using the formula y2-y1/x2-x1 (Change in y in relation to the change in x) As x changes y changes in linear.
    c=the y-intercept,where the straight line cuts on the y-axis only when x=0.

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  10. the y-intercept is point at which a line cuts the y axis and the value of x is 0.

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  11. Yes, like "shotta" said the y-intercept is point at which a line cuts the y axis and the value of x is 0.

    Solution to Questions above.
    1)3
    2)5
    3)-6
    4)3/2
    5)1/3
    6)7/2
    7)11/3
    8)7/2
    9)-1/2
    10)-5/2

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  12. My easy example!!!

    -6x + 3y - 72 = 0

    First make y the subject of the forumla

    3y = 6x + 72
    y = 6x/3 + 72/3
    y = 2x + 24

    using y = mx +c
    so
    gradient = 2
    and
    y intercept = 24

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  13. y = 6x + 3

    The y intercept in the equation above is 3 because it is already in the form of y = mx + c

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  14. y = -12x + 5

    This equation is similar to the first because it is already in the form of y = mx + c

    So the y intercept is 5 which is c

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  15. y = 2x - 6

    The y intercept in this equation is -6 .

    someone please correct me if I am wrong.

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  16. The y-intercept of a line on a graph is where the line touches (or intercepts) the y-axis (the numbered line going straight up). If the equation of the line is y = mx + c, the y-intercept will be the point where x = 0. Because 0 times anything is just 0, y = c. This is why c is the y-intercept.

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