The Angle of elevation of th top of a vertical tower from a point on the ground is 60o.From another point 10m vertically above the first, its angle of elevation is 30o.Find the height of tower? ...................Please provide me answer as soon as possible....
Let AB be the tower, D be the point from where the angle of elevation to the top of the tower is 60o, E be the point, 10 m vertically above D, from where the angle of elevation is 30o.
Draw a perpendicular fromE intersecting AB at C.
Tan 30o= 1/ 1.73= AC/EC
EC= AC* 1.73m.......(1)
Tan 60o= 1.73= AC+ CB/EC= AC+10/EC [since ED=BC=1Om]
EC= AC+10/1.73 m..........(2)
From eq.s (1) & (2), AC+10/1.73 = AC*1.73 [1.73*1.73=3]
AC+1O = 3AC
Therefore height of tower(AB)= AC+BC= (5+10)m= 15m