p417 12
问题描述：
p417 12
Five different points A,B,C,D and E lie on a line in that order.The length of AD is 4.5 and the length of BE is 3.5.If the length of CD is 2,what is one possible value for the length of BC?
答
A B C D E,AD=4.5 BE=3.5 CD=2 AB+BC=AC=2.5 BC+DE=1.5
所以BC