Contact us
Choose a category below so we can get back to you as quickly as possible.
設D為BA延長線上的一點 ∵AE是三角形ABC的外角平分線 ∴∠EAC=1/2∠CAD 又∵∠CAD=∠B+∠C,∠B=∠C ∴∠EAC=∠C ∴AE‖BC
We and our partners use cookies and other technologies to analyze traffic and optimize your experience. View more info and control your cookies settings at any time in our Cookies Policy.