# 1. diagonals of a rhombus are equal 18 cm and 80 cm to find rhombus perimeter. 2. in an isosceles triangle of AVS (the basis the EXPERT) side of =25 cm, and CK=24 height see to find the basis. 3. sides of 12 cm and 20 cm, the smaller diagonal of 13 cm to find the trapeze basis in a rectangular trapeze. Help what you will be able. Write on a leaflet, so more conveniently better;)

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1. diagonals of a rhombus are equal 18 cm and 80 cm to find rhombus perimeter. Let's FIND the PARTY of the RHOMBUS: a ²= (18/2)²+ (80/2)²=81+1600=1681=41²; a=41; P=4·a=4·41=164 2. in an isosceles triangle of AVS (the basis the EXPERT) side of =25 cm, and CK=24 height see to find the basis. b=2 √ (25²-24²) =2 √ [(25-24)(25+24)]=2·7=14 3. sides of 12 cm and 20 cm, the smaller diagonal of 13 cm to find the trapeze bases in a rectangular trapeze. A B------------- DB=13 AD=12 of BC=20 I /I the bases of a trapeze are AB, DC I /I I/ AB²=BD²-AD²=13²-12²=5² AB=5 of I/ I I/ I D = H = With DC=DH+HC, DH=AB, BH=AD HC = √ (BC²-BH²)= √ (20²-12²)= √ (8·32) =16 AB=5 DC=5+16=21,
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