a) ΔADC, mas<D= 90⁰
AD=5cm (c₂)
DC²= AC²-AD²
CD²=10²-5²
CD=√75=5√5cm (c₁)
ArieΔ= [tex] \frac{ c_{1} * c_{2} }{2} [/tex]
ArieΔ= [tex] \frac{5* 5\sqrt{3} }{2} = \frac{ 25\sqrt{3} }{2} cm^{2} [/tex]
b) fie BE_|_AC, E∈[AC]
Revin la ΔADC dreptunghic. AD=5cm, AC= 10cm
⇒mas<C= 30°
d(B,AC)=BE
ΔBEC, mas<E=90°
BC= 12cm, mas<C= 30° =>[Th.30.60.90.]BE= [tex] \frac{BC}{2} = \frac{12}{2} = 6cm [/tex]
