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11.4 Areas of Kites and Related Figures. Two formulas. A kite = A △ ABD + A △ DBC. A. DB = 10m AE = 5 m EC = 12 m BC = 13m <BAD is a right angle. D. B. E. Find the area of the kite. C. Use correct formula. A kite = A △ABD + A △ DBC = ½ (BD)(AE) + ½(BD)(EC)
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Two formulas A kite = A △ABD + A△DBC A DB = 10m AE = 5 m EC = 12 m BC = 13m <BAD is a right angle D B E Find the area of the kite. C
Use correct formula A kite = A △ABD + A △ DBC = ½ (BD)(AE) + ½(BD)(EC) = ½(10)(5) + ½ (10)(12) = 25 + 60 = 85 m2
T105: The area of a kite equals half the product of its diagonals. A kite = d1d2 A kite = ½(10)(17) = 85m2
Find the area of a kite with diagonals 9 and 14 Draw, label, write all steps.
Find the area of a rhombus whose perimeter is 20 and whose longer diagonal is 8.
What do you know about the inside triangles? 4 3 5 5 Remember: a rhombus is a parallelogram so the diagonals bisect each other. It is also a kite, so its diagonals are perpendicular to each other.