The building was taller after demolition? Very unusual.
Still, ratio of sides in a 30-60-90 triangle is 1:√3:2
So, the height changed from 120/√3 to 120√3
The difference is thus 120(√3-1/√3) = 138.56 m
When a building under construction was observed from a point P on the ground which isi 120 meters away from its base, the angle of elevation of the top was 30°. Ater is demolition, when it was again observed from the same point in the angle changed to 60°. How much higher was the building raised, from the time it was first observed?
1 answer
2 answers