Results 1 to 4 of 4

Thread: Please help with geometry hw

  1. #1
    Dec 2009

    Please help with geometry hw

    LAST PROBLEM- i dont get it at all!
    Attached Thumbnails Attached Thumbnails Please help with geometry hw-variable.bmp  
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Jul 2009
    your image doesnt enlarge. i zoomed in and i think i see
    80 4 x 7 35 5 7 y w z 5 v o 4
    is this correct?
    if it is then we begin with triangle 80 4 x 7

    a straight line is 180* with itself so the angle next to 80 is 180-80=100

    angles in a triangle add up to 180 so


    now the other triangle.
    the other triangle has 3 sides the same as this triangle so its the same triangle.

    because of the two parallel lines

    again straight lines give 180* so
    you can finish up
    Follow Math Help Forum on Facebook and Google+

  3. #3
    MHF Contributor
    Dec 2009
    Hi Idontgetit,

    Do you remember when you drew a triangle with a compass and ruler?
    If you were given the 3 side lengths, you'd have drawn one side,
    then used your compass to draw circles at the ends of that line, whose
    radii were the lengths of the other 2 sides.
    You could then see that the triangle was unique, as you were left with
    a pair of identical triangles, whose corresponding angles and corresponding side lengths were all the same.

    If you are unfamiliar, then you should draw this for any triangle you like.

    In your diagram, as pointed out by Krahl, the 2 triangles have all 3 sides of the exact same lengths, therefore these triangles are identical.
    Or you could say, we have the same triangle in 2 different positions.

    Be sure about this first.

    Now, if you imagine the triangle on the left is hinged to the double-ended arrow and you can turn it about that hinge, then you may rotate this triangle until it is in the exact same orientation as the second triangle.
    Doing this causes "x" to correspond with "u",
    35 degrees to correspond to "w",
    the unmarked angle to correspond with "v", which is 180-80=100 degrees.

    The angle "y" equals the angle "u" also if you understand the angles when
    you cross 2 parallel lines with a single line.

    Finally, z is 180-(w+y) degrees.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Member integral's Avatar
    Dec 2009
    $\displaystyle u=x$
    $\displaystyle w=35$
    $\displaystyle v=80$
    $\displaystyle x=(80+35)-180$
    $\displaystyle y=\frac{7sin(x-90)}{7}$

    $\displaystyle z=(y+w)-180$

    note: that the left most triangle is just the right triangle at a different orientation.
    Last edited by integral; Dec 26th 2009 at 08:32 PM. Reason: typo
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. [SOLVED] Finite Geometry: Young's Geometry
    Posted in the Advanced Math Topics Forum
    Replies: 0
    Last Post: Sep 15th 2010, 07:20 AM
  2. geometry
    Posted in the Geometry Forum
    Replies: 2
    Last Post: Dec 21st 2009, 03:18 AM
  3. Modern Geometry: Taxicab Geometry Problems
    Posted in the Differential Geometry Forum
    Replies: 0
    Last Post: Mar 30th 2009, 07:32 PM
  4. geometry
    Posted in the Geometry Forum
    Replies: 3
    Last Post: Nov 17th 2008, 05:29 PM
  5. geometry
    Posted in the Geometry Forum
    Replies: 13
    Last Post: Jun 8th 2008, 07:31 AM

Search Tags

/mathhelpforum @mathhelpforum