i have a doubt in trignometry .please explain me.

let AB be the light house with A as the top.

let C and D be te positions of the two ships.

so acc to question,

ange CAB=60

 and angle DAB=45

LET cb=X

 and

 DB=y

so

tan 60=h/x

tan 45=h/y

x=

..(i)

and

y=h...(ii) but

x+y=

so

y=-x....(iii)

from (i), (ii) and (iii) we can find h