+0  
 
0
631
1
avatar

A superhero is running toward a skyscraper to stop a villain from getting away. As he is moving, he looks up at the top of the building and his line of sight makes a 33.0° angle with the ground. After having moved 350 m, he looks at the top of the building again, and notices that his line of sight makes a 52.0° angle with the horizontal. How tall is the skyscraper?

 Jul 3, 2016
 #1
avatar+129842 
0

Let  m be the total distance he is from the skyscraper when he first sights it...and let h be the height of the skyscraper......so we have.....

 

tan (33) = h/m        →  m =    h/tan (33)

 

After he runs 350m....he is (m - 350)m from the skyscraper

 

And we have that

 

tan (52)  = h / [ m - 350]        substitute for m  to get an equation in one variable

 

tan (52)  = h / [ h/tan (33) - 350]          multiply both sides by  [ h/tan (33) - 350]  

 

[ h/tan (33) - 350]  * tan (52)   = h        simplify

 

h [ tan(52)/tan(33) ] - 350 * tan(52)   = h        rearrange  and factor

 

h [ tan (52) / tan(33)  - 1 ]  =  350 * tan(52)     divide both sides by [ tan (52) / tan(33)  - 1 ] 

 

h =  350 * tan(52)  / [ tan (52) / tan(33)  - 1 ]   ≈ about 461.39 m

 

 

 

cool cool cool

 Jul 3, 2016

2 Online Users

avatar
avatar