Question

Ip: ΔABC
m(∡A)= 90°
AC= 20 cm
BC= 25 cm
M- mij. AC
N∈ CN a. i. CN= 8 cm
Cc: Aratati ca MN⊥ BC





VA ROG AJUTORRRRRR! URGENT!

Answer 1

MC=AC/2=20/2=10         
CN=8
AB=√(25²-20²)=√(625-400)=√225=15 cm
Aria triunghiului ABC=15×20/2=150 cm²
inaltime AD_I_BC
AD=150×2/25=12 cm
DC=√(20²-12²)=√(400-144)=√256=16 cm
CN/DC=8/16=1/2
MC/AC=10/20=1/2
rezulta ca MN II AD  dar AD _I_ BC  ⇒ ca si MN _I_BC