Question

ABC is an isosceles triangle in which AB=BC. a circle passing through B and C intersects the sides AB and AC at D and E respectively. prove that DE//BC

Answer 1

Answer:

As we know that △ ABC is an isosceles triangle,

AB = AC and a circle passing through B and C intersects AB and AC at D and E So AB = AC We get ∠ACB = ∠ABC It can be written as ∠ADE = ∠ACB = ∠ABC So we get ∠ADE = ∠ABC DE || BC Therefore, it is proved that DE || BC.