Question

solve 4th question plz

Answer 1

proof: since ABCD is a ||gm
AB||DC &AD||BC
now,ABll RS, ARllBS

ABSR is a llgm
similarly,we can prove that RSCD is a also llgm
now,∆APB &llgm ABSR are lie on the same base AB and b/w same ll ABllRS

ar(∆APB)=1/2 ar(ABSR)-1
similarly,ar(PCD)=1/2ar(RSCD)-2

adding 1and2,we get-
ar∆APB*ar(∆PCD)=1/2[ar(ABSR)*ar(RSCD)]

ar(∆APB)*ar(∆PCD)=1/2ar(ABCD)

hence proved
thanks