八年级 数学 几何题 急求!题目https://onedrive.live.com/redir?resid=64326FB3945C05B2!1975&authkey=!AAFmdNmM6WiofBU&v=3&ithint=photo,.jpg

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八年级 数学 几何题 急求!题目https://onedrive.live.com/redir?resid=64326FB3945C05B2!1975&authkey=!AAFmdNmM6WiofBU&v=3&ithint=photo,.jpg
八年级 数学 几何题 急求!
题目https://onedrive.live.com/redir?resid=64326FB3945C05B2!1975&authkey=!AAFmdNmM6WiofBU&v=3&ithint=photo,.jpg

八年级 数学 几何题 急求!题目https://onedrive.live.com/redir?resid=64326FB3945C05B2!1975&authkey=!AAFmdNmM6WiofBU&v=3&ithint=photo,.jpg
因为DE∥AB所以角BAD=∠ADE,又因为AD是∠BAC的角平分线所以∠BAD=∠EAD,∴∠EAD=∠EDA,∴AE=ED,又∵BF=AE,∴BF=DE,且DE∥BF,∴四边形BFDE为平行四边形,所以EF∥BD.