Isosceles Trapezoid: If the legs of the trapezoid are congruent then the trapezoid is an Isosceles trapezoid.
- Is a quadrilateral with exactly one pair of parallel sides. The parallel sides are the bases
- A trapezoid has two pairs of base angles. For example in the trapezoid ABCD,
ÐA and ÐB are one pair of base angles, and ÐC and ÐD are the second pair.
- The non parallel sides are the legs of the trapezoid.
- If a trapezoid is isosceles, then each pair of base angles is congruent.
If trapezoid ABCD is isosceles, then ÐA @ ÐD and ÐB @ ÐC.
- If a trapezoid has a pair of congruent base angles, then it is an isosceles trapezoid ABCD is isosceles.
If ÐA @ ÐD and ÐB @ ÐC. then ABCD is isosceles.
- A trapezoid is isosceles if and only if its diagonals are congruent.
Trapezoid ABCD is isosceles if and only if AC @ BD.
- Midsegment Theorem for Trapezoids:
The midsegment of a trapezoid is parallel to each base and its length is one half the sum of the lengths of the bases. If MN is the midsegment of trapezoid ABCD, then MN // AB, MN // DC, and MN = 1/2(AB+CD)
1) For the trapezoid ABCD shown below find the measures of angle A, angle C and angle D.
2) Answer the following questions and write at least 5 examples of your own.