Trapezoid

• A quadrilateral with ONLY ONE pair of parallel sides, which are called BASES.

• Trapezoids include:

  • 2 pairs of base angles.

  • Non-parallel sides are called LEGS.

Isosceles Trapezoid

• A Trapezoid with CONGRUENT LEGS.

• Properties include:

  • Each pair of base angles are congruent.

  • Diagonals are congruent, but do NOT bisect each other.

∠D= 115, ∠E= 115, ∠F= 65

CDEF is an isosceles trapezoid where ∠C=65°. Find the values of ∠D, ∠E, and ∠F.

Example #1

Find the value of x in the isosceles trapezoid STWR.

Example #2

​**What do we know about the base angles of an isosceles trapezoid?

60 = 5x

In the previous chapter, we learned about midsegments of triangles... Well guess what?Trapezoids have midsegments, too!!

Midsegment of a Trapezoid

• The segment that joins the midpoints of a trapezoid's legs.

Example #3 - QR is the midsegment of trapezoid LMNP. Solve for the value of x.

​x+2 = 1/2 (4x-10+8)
x+2 = 1/2 (4x-2)
x+2 = 2x-1
+1 +1
x+3 = 2x
-x -x
3 = x