1.Calculaati aria unui triunghi ABC de inaltime AD, stiind ca:
a) BC= 4 cm; AD= 6 cm;
b) Bc= 20mm;AD=0,3 dm;
c) AD=40 cm;
BC=3supra 5 AD
d) BC=1cm;Ad=20%BC
2.Calculatii:
a)aria unui triunghi dreptunghic cu cateterle egale cu 4 cm si respectiv 6 cm.
b) aria unui triunghi dreptunghic isocel cu o cateta egala cu 6 cm.

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Răspunsuri

2014-11-17T14:10:06+02:00
1.
a)Aria triunghiului=B·h/2;AD=h;BC=B⇒A=B·h/2=4·6/2=12cm²
b)BC=20mm=2cm;AD=0,3dm=3cm⇒A=B·h/2=3cm²
c)AD=40cm;BC=3/5·AD=3/5·40=24cm⇒A=B·h/2=480cm²
d)BC=1cm;AD=20/100BC=2/10BC=0,2cm⇒A=B·h/2=0,2cm²
2.
a)Aria triunghiului dreptunghic=C₁·C₂/2=4·6/2=12cm²
b)Triunghiul=dreptunghic isoscel;C₁=6 cm⇒C₂=C₁=6cm;Aria=C₁·C₂/2=18cm²

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