前两图:AD=根号(13^2-5^2)=12,AD×BC=AC×BE,BE=120/13
题号1:BD=3,AB=5,则AD=4,面积4×6/2=12
题号2:BD=根号(26^2-24^2)=10,CD=根号(25^2-24^2)=5,CB=10+5=15
题号3:CB=根号(13^2-12^2)=5,CD×AB=AC×BC,CD=12×5/13=60/13
前两图:AD=根号(13^2-5^2)=12,AD×BC=AC×BE,BE=120/13
题号1:BD=3,AB=5,则AD=4,面积4×6/2=12
题号2:BD=根号(26^2-24^2)=10,CD=根号(25^2-24^2)=5,CB=10+5=15
题号3:CB=根号(13^2-12^2)=5,CD×AB=AC×BC,CD=12×5/13=60/13