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Warm up. 3.7 Midsegments of Triangles & Trapezoids. FYI 3.7 today 3.8 next time Review the time after that... Then… Chapter 3 test the time after that. C. midsegment. B. ½ X. D. A. E. X. Midsegment of a triangle .
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3.7 Midsegments of Triangles & Trapezoids FYI 3.7 today 3.8 next time Review the time after that... Then… Chapter 3 test the time after that
C midsegment B ½ X D A E X Midsegment of a triangle • A segment whose endpoints are the midpoints of two sides. It is parallel to one side of the triangle and its measure is ½ of that side. If AE = 15 Find the measure of BD BD = 7.5
C 3X - 5 A E B X D X + 2 B D A E C X2 + 1 TRY THIS 3X – 5 = 2(X + 2) 3X – 5 = 2X + 4 X = 9 AE = 22 units BD = 11 X2 + 1 = 2 (X) X2 – 2X + 1 = 0 (X – 1) (X – 1) = 0 X = 1 BD = 1 units AE = 2 units AND THIS
BASES Midsegment Midsegment of a Trapezoid • A segment whose endpoints are the midpoints of the NON-PARALLEL sides. • It’s parallel to the bases and • its measure = (Sum of the bases) 2
X A M X + 5 B Y ? C Z YEA!! Try this Find the lengths of the parallel segments when x = 2 AM = 2 BY = 7 CZ = 12 Check to make sure these numbers work… Find ? 2 + 12 = 7 2 ? = X + 10
Try this… If AZ = 25 and CX = 31, find BY Z BY = 28 and this… C X If AZ = x2 + 4x - 36 and CX = x2 + 2x - 40 and BY = 16 Find the lengths of the bases Y B A
C B D A E Uno mas Find the lengths of BD and AE if BD = 4x – 4 and AE = 10x – 12 2(4x-4) = 10x – 12 8x – 8 = 10x -12 4 = 2x X = 2 BD = 4 AE = 8
Assignment Pg 186, 5-8, 10-16, 22, 28-30, 32-40