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Dimensions of rectangle from coordinates example

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    - [Voiceover] Rectangle ABCD is graphed
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    in the coordinate plane.
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    The following are the
    vertices of the rectangle,
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    and they give us the labels
    for the vertices as well.
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    Given these coordinates,
    what is the length
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    of side AD of this rectangle?
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    So let's just plot it.
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    That's one way that we could tackle it.
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    So let's, let me see,
    all of these are actually
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    in the first coordinate,
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    so I could focus on the first coordinate.
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    So let's say that's my y-axis.
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    It's my y-axis, and let me draw my x-axis.
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    My x-axis, and actually
    I wanna really focus in
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    on the points A and D,
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    because we just need to
    find the length of the side
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    from point A to point D.
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    So point A, let me do
    this in another color.
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    So point A is at x equals seven,
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    y is equal to one.
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    So one, two, three, four,
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    five, six, seven, so
    that's x equals seven.
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    Y is equal to one.
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    Y is equal to one, so that
    is point A right over there.
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    Point A, let me label it. Point A.
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    And then where's point D?
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    Point D has the exact same x-coordinate,
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    but its y-coordinate
    is a little bit higher.
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    Its y-coordinate is six.
    It's actually five higher.
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    So point D is at x equals seven,
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    y is equal to six.
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    So y is equal to one, two, three,
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    four, five, and six.
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    So that's y is equal to six,
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    and so we can draw the point.
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    It is going to be right over here.
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    This is point D,
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    and we could actually connect
    them with a line, if we like,
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    to show that this is
    a side of a rectangle.
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    Let me draw that. I can
    just draw this like this.
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    And there you have it.
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    I haven't even drawn
    the whole rectangle yet,
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    but just by plotting these two points,
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    we can think about how long side AD is.
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    We could say, look, the x
    doesn't change going from A to D,
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    but we do increase in
    the y direction by five.
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    We go from y is equal to
    one to y is equal to five,
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    to y is equal to six.
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    So our change in y is equal to five.
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    So what's the length of this line?
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    Well, it's gonna be five.
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    It's gonna be five,
    whatever the units are.
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    So that's the length of side AD.
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    It's going to be equal to five.
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    We went from the point (7, 1)
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    to the point (7, 6).
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    Now, they said that this was a rectangle.
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    Now, just for our satisfaction,
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    we can draw the entire rectangle.
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    We have that point B
    that is at x equals five,
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    y is equal to one, so let me draw that.
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    And I'm just doing this just
    for fun now at this point.
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    We're done with the problem.
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    So x equals five, y equals
    one. That's right over here.
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    That's point B.
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    Let me write B. That's the point (5, 1).
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    And then we have the point C.
    I'll do this in another color.
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    The point C is at x
    equals five, y equals six.
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    X equals five, y equals six.
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    Point C is right over here.
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    Point C is the point x equals
    five, y is equal to six.
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    And then we could connect
    all the dots, if we like,
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    and clearly see that it is a rectangle.
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    So I could connect those.
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    I could connect these two.
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    Then I could connect these two.
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    And then we see that we
    indeed have a rectangle.
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    But we answered it awhile
    ago that the length
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    of side AD is equal to five.
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    If we cared about the other sides,
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    the length of BA, well, this is two.
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    a difference of two along the x direction,
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    the horizontal direction,
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    difference of two along the x direction,
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    difference of five in the y direction.
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    We go from y equals one to y equals six.
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    So there you have it.
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    We actually will figure
    out all of the dimensions
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    of this rectangle.
Title:
Dimensions of rectangle from coordinates example
Description:

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Video Language:
English, British
Duration:
03:51

English subtitles

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