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Trapezoids. 6-6 p.389. Trapezoids. A quadrilateral with exactly ONE pair of parallel sides Parallel sides are called bases Other 2 sides are called legs Angles that share a base of a trapezoid are called base angles (2 pair). Base. Base Angles. Leg. Leg. Base. Base Angles.
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Trapezoids 6-6 p.389
Trapezoids • A quadrilateral with exactly ONE pair of parallel sides • Parallel sides are called bases • Other 2 sides are called legs • Angles that share a base of a trapezoid are called base angles (2 pair) Base Base Angles Leg Leg Base Base Angles
Isosceles trapezoid Base • Definition- A trapezoid with congruent legs • Base angles of an isosceles trapezoid are congruent (Thm 6-19) • Diagonals of an isosceles trapezoid are congruent (Thm 6-20) Leg Leg Base
Median (midsegment) of a trapezoid • Definition- segment that joins the midpoints of the legs of a trapezoid • The median (midsegment) of a trapezoid (Thm 6-21) • Is parallel to the bases (MN||DC) • Has a length equal to the average of the base lengths MN= (AB + DC)/2 B A N M D C
Example 12 • For the trapezoid and its median (midsegment) shown above, find x. • x = (12 + 30)/2 = 21 x 30
Kites • Definition- A kite is a quadrilateral with two pairs of consecutive sides congruent and no opposite sides congruent. • Diagonals of a kite are perpendicular (Theorem 6-22)
Homework • p.394-395 #7-15 odd, 16-24 all • p.396 #47-52
More Practice • Properties of Trapezoids worksheet (1-18 all) • Trapezoids worksheet