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Homework Help: Please Help Me In What My Teacher Said Is Easy

  1. Jan 4, 2005 #1
    Find the value of x. Show all work with justifications.

    Attached Files:

  2. jcsd
  3. Jan 4, 2005 #2


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    The sum of the three angles in a triangle is 180 degrees. The sum of two angles making a line is also 180 degrees: that leads to the well known theorem (it's probably in your text) that the measure of an external angle (here the one marked "125") is equal to the sum of the measures of the two opposite angles. One of those two opposite angles is 50 degrees. From that you can find the measure of the angle between "80" and "x" and then find x.
  4. Jan 5, 2005 #3
    Are there any "formulas" to find "x" in this particular problem?......
  5. Jan 5, 2005 #4
    Not that I know of
  6. Jan 5, 2005 #5


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    Beside this one
    [tex] A+B+C=180° [/tex]
    ,where A,B,C are the three angles of a plane triangle,nope.
    But,as Ivy said,u need to know that the sum of two supplementary angles is 180°.

    This is all u need to know to get it done.

  7. Jan 5, 2005 #6
    Again there are no formulas to solve this problem, it is all geometrical.

    Step one.
    Look at the angle 125. 180-125 will give you the angle on the other side of the line.

    Step two add 55+50 and minus the product from 180. this is the upper angle.

    Step three add 80+75 then minus that from 180 and that is the angle x
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