Salut....va rog mult ajutati-ma cu acest exercitiu.....Triunghiul dreptunghic ABC,m(A)90*,ADperpendicular pe BC,D apartine laturii(BC),are AB|AC(supra)=3|4(3 supra 4),aria este egala cu 216cm(la 2).Aflati:
a)perimetrul
b)lungimea inaltimii AD
c)lungimea segmentelor BD,CD.
Va multumesc!

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Răspunsuri

2014-04-18T16:01:34+03:00
A=c1*c2/2=216
c1*c2=432
AB/AC=3/4
AB=3AC/4
AB*AC=432
3AC/4* AC=432
3AC²=4*432
AC²=4*432/3
AC²=576
AC=24
AB=3*24/4=18

ΔABC,mas<A=90
BC²=AB²+AC²=18²+24²=576+324=900   ⇒BC=30

AD=AB*AC/BC=  24*18/30=432/30=  144/10

AB²=BD*BC
18²=BD*30
324=BD*30
BD=324/30=108/10
DC=30 -108/10  aducem la acelasi numitor
DC=300-108/10
DC=192/10=96/5