一条渔船距对岸4 km,以2 km/h的速度向垂直于对岸的方向划去,到达对岸时,船的实际航程为8 km,求河水的流速. 答案:解:如图,设表示船垂直于对岸的速度,表示水流的速度,则由+=,就是渔船实际航行的速度,航行的时间为4 km÷2 km/h=2 h,在Rt△ABC中,||=2 km/h,| |=8÷2=4 km/h. ∴||=2 km/h. 故河水的流速为2 km/h.—What should you do if you have problems with your
life?
—
.
A.To find a
friend to talk B.Find a friend
to talk to
C.Finding a
friend to talk to D.Found a
friend to talk