Предмет: Геометрия, автор: макс14

Дано: хордыCDnAB=E AE=4 BE=6 DE>на 5 CE найти DE,CE,AB,CD

Ответы

Автор ответа: KatyaLebed98

Пусть СЕ = х см, а ЕД у см, тогда
по теореме о хордах АЕ * ЕВ = СЕ * ЕД
значит, х+5=у, ху=6*4=24
подставим первое равенство во второе

(х+5)х=24

х^2+5x=24

x^2+5x-24=0

D=25+96=121
x=(-5+11)/2
x=3
y=5
CE = 3, DE = 8

AB = 10
CD = 11

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