Question

in triangle ABC. AB = AC. A circle passing through B and C intersects AB at D and AC
at E. Prove that BC || DE.​

Answer 1

Answer:

$\huge\bold\red{Answer᭄}$

ɪɴ △ᴀʙᴄ

∠ʙ=∠ᴄ. .(1)

ɪɴ ᴛʜᴇ ᴄʏᴄʟɪᴄ ϙᴜᴀᴅʀɪʟᴀᴛᴇʀᴀʟ ᴄʙᴅᴇ, sɪᴅᴇ ʙᴅ ɪs ᴘʀᴏᴅᴜᴄᴇᴅ ᴛᴏ ᴀ.

ᴡᴇ ᴋɴᴏᴡ ᴛʜᴀᴛ ᴇxᴛᴇʀɪᴏʀ ᴀɴɢʟᴇ ɪs ᴇϙᴜᴀʟ ᴛᴏ ᴏᴘᴘᴏsɪᴛᴇ ɪɴᴛᴇʀɪᴏʀ ᴀɴɢʟᴇ.

ɪ.ᴇ ∠ᴅ=∠ᴄ. (2)

ғʀᴏᴍ (1) ᴀɴᴅ (2)

∠ᴀᴅᴇ=∠ᴀʙᴄ

sᴏ, ᴄᴏʀʀᴇsᴘᴏɴᴅɪɴɢ ᴀɴɢʟᴇs ᴀʀᴇ ᴇϙᴜᴀʟ

ʜᴇɴᴄᴇ, ᴅᴇ∣∣ʙᴄ