Question

Va rog frumos sub-punctele a,b exercițiul 2

Answer 1

a)
AB =18 cm
BC =15 cm
CA = 12 cm
AD =6 cm
P ADE= ?
In tr ABC , BC || DE => T.F.A. AD/AB = AE/AC = DE/BC
AD/AB= AE/AC
6/18= AE/12
AE = 6×12/18
AE = 4 cm
AE/AC=DE/BC
4/12=DE/15
DE =4×15 /12
DE =5 cm
P ADE= AD +AE + DE = 6 cm + 4 cm +5 cm = 15 cm

b)
AB =25 cm
BC =20 cm
CA=30 cm
DE =4 cm
P ADE = ?
In tr ABC , BC|| DE => T.F.A. AD/AB = AE/AC = DE/BC
AE/AC =DE/BC
AE /30=4/20
AE = 30×4/20
AE =6 cm
AD/AB= AE/AC
AD/25=6/30
AD= 25×6 /30
AD= 5 cm
P ADE = AD + AE + DE = 5 cm + 6 cm + 4 cm =15 cm