Midsegments of Triangles and Trapezoids

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Midsegments of Triangles and Trapezoids
Chapter 3.7
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Triangle Mid-Segment

• A segments endpoints are the midpoints of two
  sides
• Line AB is parallel to Line CD
• Line AB is half of Line CD

B
A
C
D
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Trapezoid Mid-Segment

• The segments endpoints are the midpoints of non
  parallel sides.
• Parallel to the base of a trapezoid and has a
  measure equal to one half of the sum of the base
  lengths.
• If line AB is parallel to line CD, and line CD is
  parallel to line EF, then line AB is parallel to
  line EF

A
B
E
F
C
D
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Examples

• Say that your mid-segment of a triangle is 4x2,
  and your base is 7x-6. Since the mid-segment is
  half of the base, you would set it up like this ½
  (7x-6)4x2. Then you would solve for x. In
  this case the base is -10 and the mid-segment is
  -5.
• If your trapezoid had a mid-segment of 100, and a
  base of 75, the other base would have to be 125.
  It has to be 125 because to get the mid-segment,
  you add both the bases and divide it by two. So
  12575200, 200/2100.