Question

In triunghiul dreptunghic ABC, m(a) =90 m AD perpendicular pe BC, D apartine pe BC. Daca BD=4DC si BC=15cm calculati BD,DCsi AD

Answer 1

BC = CD+BD <=> BC= CD+4 DC <=> BC = 5DC => 15= 5 DC => DC = 3 
=> BD = 4 DC = 4*3 => BD = 12
Avem: BD= 12, DC = 3 => BC = 15
Th. Inaltimii: AD$AD^{2} = BD * DC \ \textless \ =\ \textgreater \ AD^{2} = 12*3 =\ \textgreater \ AD^{2} = 36 =\ \textgreater \ AD= \sqrt{36}$ 
=> AD =6