1. Bell Ringer

2. Trapezoid A Trapezoid is a quadrilateral with exactly one pair of parallel sides. The Parallel sides are the bases The non parallel sides are the legs A trapezoid has two pairs of base angles Isosceles trapezoid- if the legs are congruent

3. Example 1 Find Angle Measures of Trapezoids PQRS is an isosceles trapezoid. Find the missing angle measures. SOLUTION PQRS is an isosceles trapezoid and  R and  S are a pair of base angles. So, m  R = m  S = 50°. 1. Because  S and  P are same-side interior angles formed by parallel lines, they are supplementary. So, m  P = 180° – 50° = 130°. 2. Because  Q and  P are a pair of base angles of an isosceles trapezoid, m  Q = m  P = 130°. 3.

4. Now You Try Find Angle Measures of Trapezoids ABCD is an isosceles trapezoid. Find the missing angle measures. ANSWER m  A = 80° ; m  B = 80° ; m  C = 100° 1. 2. 3. ANSWER m  A = 110° ; m  B = 110° ; m  D = 70° ANSWER m  B = 75° ; m  C = 105° ; m  D = 105°

5. Example 2 Midsegment of a Trapezoid Find the length of the midsegment DG of trapezoid CEFH. SOLUTION Use the formula for the midsegment of a trapezoid. DG = 1 2 ( EF + CH ) Formula for midsegment of a trapezoid = 1 2 (8 + 20 ) Substitute 8 for EF and 20 for CH. = 1 2 ( 28 ) Add. = 14 Multiply. ANSWER The length of the midsegment DG is 14.

6. Now You Try Midsegment of a Trapezoid ANSWER 11 Find the length of the midsegment MN of the trapezoid. 4. 5. 6. ANSWER 8 21

7. Now You Try

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13. Complete Pages 334-335 #s 10-30 Even Only Homelearning Page 336 #s 32-38 even only