plzz solve this question..??
Answers
Answer:
Tum konsi class mein parti ho ??
STEP BY STEP ANSWER
(1)
from triangle ∆ABD and ∆ACD,we get
AD=AD(common sides)
AB=AC(as ∆ABC is a isosceles triangle,)
BD=DC(as ∆BDC is a isosceles triangle,)
so,
∆ABD=~∆ACD(SSS congruency)(proved)...(I)
therefore,<BAD=<CAD(cpct)
or,<BAE=<CAE
i.e., AD bisects <A .
∆ABC is a isosceles triangle,and AD bisects <A .
so AD or AE is the median of ∆ABC,
so,BE=CE
(2)
from triangle ∆ABE and ∆ACE,we get
AE=AE(common sides)
<BAE=<CAE(proved earlier)
AB=AC(as ∆ABC is a isosceles triangle,)
so,
∆ABE=~∆ACE(SAS congruency)(proved)
(3)
from triangle ∆BDEand ∆CDE,we get
DE=DE(common sides)
BE=CE(proved earlier,)
BD=DC(as ∆BDC is a isosceles triangle,)
so,
∆BDE=~∆CDE(SAS congruency)(proved)
so,
<BDE=<CDE(cpct)
i.e., DE bisects <D or AE bisects <D (proved)
and from previous
or,<BAE=<CAE
i.e., AD bisects <A or AE bisects <A (proved)
(4)
now ,∆BDE=~∆CDE
so <DEB=<DEC(cpct)
<DEB+<DEC=2 right angle
2<DEB=2 right angle
<DEB=1 Right angle
i.e.,DE perpendicular to BC
or AE perpendicular to BC(proved)