Question

Am nevoie rapid de rezolvarile de la ex:1,2,3.

Answer 1

1.∆ ABC dreptunghic cu AD inaltimea din A

AB=15 cm. BD=9cm

perimetru ABC=

AD=√15²-9²=12cm

AD²=BD×DC=>DC=12²/9=16cm=>BC=9+12=21cm

AC=√21²-15²=6√6cm

a)perimetru ABC=15+21+6√6=36+6√6

aria ABC=15×6√6=90√6cm²

b)aria ADB/CDA=12×9/12×16=9/16

c) aria∆CDA______100

aria∆ADB_______x=9×100/16=56,25%

2..∆ ABC dreptunghic cu AD inaltimea din A

∆ ABD dreptunghic DC=√60²-36²=48cm

AD²=BD×DC. 36²=BD ×48. BD=36²/48=27cm

BC=48+27=75cm. AB=√36²+27²=45cm

a)perimetru ABC=45+75+60=180,cm

aria ABC=60×45/2=1359,cm²

........se repetă

3.∆ ABC dreptunghic cu AD inaltimea din A

.....la fel