Please answer me question 15 and 16

Please answer me question 15 and 16 to tix a a: "T f taken the thi.

15) let AB be the tower , x be the time taken to reach the tower of the foot from that point and y be the constant speed

     distance = speed * time
     CD = y * 6
     CD = 6y
​     similarly,
     CB = xy

    tan 30 = AB / BD
               = AB / CB +CD
    1/sqrt(3) = AB / y (6+x)
    AB = y (6+x) / sqrt(3)

Now,
     tan 60 = AB / BC
                =y (6+x) / sqrt(3) * 1/xy
​     sqrt (3) = (6+x) / sqrt(3) * 1/x
     sqrt(3) * x = 6+x / sqrt(3)
     3x = 6+x
     2x = 6
     x = 3
   
    Therefore the car will take 3 more seconds to reack the foot