Question

$\text{In the given figure,}\angle B<\angle Aand\angle C<\angle D.\text{Show that}AD<BC.$

Answer 1

Given: ∠ B < ∠ A and ∠ C < ∠ D
To prove: AD > BC
Proof:
In ∆AOB,∠B<∠A⇒AO<BO Side opposite to the greater angle is longer .....1
In ∆COD,∠C<∠D⇒OD<OC Side opposite to the greater angle is longer .....2
Adding (1) and (2), we getAO+OD<BO+OC

∴AD<BC