Cho tam giác ABC có AB=AC. Tia phân giác của góc A cắt BC ở D a) Chứng minh tam giác ABD = tam giác ACD
b) Chứng minh AD vuông góc với BC
c) Vẽ DH vuông góc với AB( H thuộc AB), DK vuông góc với AC( K thuộc AC)
Chứng minh DH=DK

Will mark brainliest question in the pic.

Monica build a remote control toy airplane for science project to test the plane she launched it from the top of a building the plane travel a horizontal distance of 50 feet before landing on the ground a quadratic function which models the height of the plane in feet relative to the ground at a horizontal distance of x feet from the building is shown

Every weekday, mr. jones bikes from his home to his job. sometimes he rides along two roads, the long route that is shown by the solid lines. other times, he takes the shortcut shown by the dashed line. how many fewer kilometers does mr. jones bike when he takes the shortcut instead of the long route?