Question

❌Class 10 : Triangles chapter. Please help !❌​

Answer 1

$\frac{ar(∆ADE)}{ar(∆ABC)}=(\frac{DE}{BC})^2$

$\frac{ar(∆ADE)}{ar(∆ABC)}=(\frac{5}{8})^2$

$ar(∆ADE) : ar(∆ABC) = 25 : 64$

$Now ,$

$Area \: of \: trapezium \: BCED :-$

$=> ar(∆ABC) - ar(∆ADE)$

$=> 64 - 25 = 39$

$So , ar(BCED) : ar(∆ABC) = 39 : 64$