Trapezoid Study Guide

A trapezoid is a quadrilateral with exactly one pair of parallel sides.The parallel sides are called bases and the nonparallel sides arecalled legs.

An isosceles trapezoid is a trapezoid whose legs are congruent..:. The diagonals of an isosceles trapezoid are congruent. ,_

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The median of a trapezoid is the segment that joins the midpointsof the legs. The median is parallel to the bases and its measure ishalf the sum of the measures of the bases.

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ABCD is an isosceles trapezoid. MN is a median.

Ex. 1 AS = 30, CD = 42, MN = 3~Ex. 2 AB = 18, MN = 25, CD = .3~

Ex. 3 AB = 6x - 3; MN = 15; CD = ax + 5.

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\SS+~ =- 50Find x, AS, and CD.

Ex. 4 mLl = 4x - 60; mLC = 30 - x.

It;. 'f..=- 28

y., =: ~A~=- q

./ CO=-d-.\Find x, mz l, and mLC.

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Ex. 5 mLB = 4x + 40, mLD = 3x. find x, mLB, and mLD.

4~..(-~o+ 30 = ,go- \~Of 'f.. -

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\E Base F

median

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Ex. 7 Given: ~9sceles trapezoid ABeD, mLABD = 20°, mLDAC = 75°. (Note that an isosceles.-- ..~~~

trapezoid has Q lineOf symmetry.)

mLl= J.OmL2= 15mL3= ifomL4= \fo

mL5= ~SI) .-d.O .' C.

mL6=

mL7= 65mL8= :).0mLDAB= q~

mLABC= qS-m~,.o.DC; S§mLBCD = ~S

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Trapekoid Study Guide.-,

A trapezoid is a quadrilateral with exactly one pair of parallel sidesThe parallel sides are called bases and the nonparallel sides arecalled legs.

An isosceles trapezoid is a trapezoid whose legs are conqruent.

The median of a trapezoid is the segment that joins the midpointsof the legs. The median is parallel to the bases and its measure ishalf the sum of the measures of the bases.

A BCD is an isosceles trnpezoid. MN is a median.

Ex. 1 AB = 30, CD = 42, MN = ~

Ex.2 AS = 18, MN:: 25, CD = _

Ex. 3 AS = 6x - 3;MN = 15; CD = 8x + 5. Find X, AS,and CD.

Ex.4 mz l > 4x - 60; m;;:C:= 30 - x. Find x, mz'L, and mZC.

https:llowa.fortbend.k12. tx.us/exchange/004sm364/Inbox/trapezoids%20: ).EML/Trapezoi... 1/27/2010