please solve this for me
Answers
41) D
Explanation- since its given that its isosceles, and that AB⊥BC, we can conclude that BD= DC. then BD= BC/2= 8cm.
it is also given that ΔADB is right angled.
Using Pythagoras Theorem,
AD²+BD²= AB²
AD²=AB²- BD²
AD²= 100-64
⇒AD = 6cm
It is also given that ΔADC is right angled.
Using Pythagoras theorem,
AD= 6cm
DC= BD= 8cm
AC²= 6²+8²= 100
AC= 10cm
simply, by looking at question we can conclude that AC= 10cm, because AC= AB.
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42) C
Explanation- semi perimeter = AB+BC+AC/2
⇒ semi perimeter = 10+10+16/2= 18cm
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43) D
Explanation- Area= B×H/2
16×10/2
80cm.
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44) A
i have explained the derivation of the length of AD in 41st question, please check with that.
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Thank you!