230 likes | 414 Views
6.5 Trapezoids & Kites. Trapezoid. Is a quadrilateral with exactly 1 pair of parallel sides. BASE. base angle. base angle. leg. leg. base angle. base angle. BASE. Trapezoid. A B. C D. If the legs are congruent then the trapezoid is an isosceles trapezoid. Theorem 6.14.
E N D
Trapezoid • Is a quadrilateral with exactly 1 pair of parallel sides
BASE base angle base angle leg leg base angle base angle BASE Trapezoid A B C D
If the legs are congruent then the trapezoid is an isosceles trapezoid.
Theorem 6.14 • If a trapezoid is isosceles, then each pair of base angles is congruent.
Theorem 6.15 • If a trapezoid has a pair of congruent base angles, then it isan isosceles trapezoid.
Theorem 6.16 • A trapezoid is isosceles if and only if its diagonals are congruent.
Midsegment • The midsegment of a trapezoid is the segment that connects the midpoints of its legs.
THM 6.17 • The midsegment of a trapezoid is parallel to each base and its length is one half the sum of the lengths of its bases
EX 1 Find the length of MN. 10 16 P Q 13 M N S R
EX 2 Find the value of x. 19 15 17 x
A Kite • A quadrilateral with two pairs of consecutive congruent sides, but opposite sides are not congruent.
Theorem 6.18 • If a quadrilateral is a kite, then its diagonals are perpendicular.
Theorem 6.19 • If a quadrilateral is a kite, then exactly one pair of opposite angles is congruent.
Ex 3 Find the measure of the sides. Round to the nearest tenth. LM = 3.6 LO = 3.6 ON= 5 MN = 5 L 2 O M 3 3 4 N
Ex 4 Find the mL. 110 L M 100 40 O N
Ex 5 Find the mL. 35 L M x 55 O 135 N
5.4 Midsegment Theorem Goal: Identify midsegments and use properties of midsegments of a triangle
Midsegment – a segment that connects the midpoints of two sides of a triangle.
MidsegmentTheorem The segment connecting the midpoints of two sides of a triangle is parallel to the third side and half as long. B X Y AC || XY XY = ½ AC A C
Ex 1: UW and VW are midsegments of RST. Find UW and RT. R U UW = 6 V 12 8 RT = 16 T W S
Ex 2: X, Y, and Z are the midpoints of UVW. Complete each statement. • If VW = 6a, then XY = ___ • b. mWZY = 2b + 1, then mWVU = ______. • c. XZ _______. • d. If YZ = c, then UV = ____ U X Y W V Z