It is dangerous for teenagers to give out too much about themselves on the Internet.
A:information
B:questions
C:ideas
D:knowledge
如图,△ABC与△ADC中,∠B=∠D=90°,要使△ABC≌△ADC,还需添加的一个条件是____ (写出一个即可).
如图,两根电线杆相距Lm,分别在高10m的A处和15m的C处用钢索将两杆固定,求钢索AD与钢索BC的交点M离地面的高度MH.
已知1a+1b=5(a≠b),求aba-b-baa-b的值.