I WILL FAN
13. A ladder leans against a building. The angle of elevation of the ladder is 70°. The top of the ladder is 25 ft from the ground.

To the nearest tenth of a foot, how far from the building is the base of the ladder?
(Points : 5)
20.5 ft
30.5 ft
32.3 ft
39.5 ft

Question

I WILL FAN 
13.  A ladder leans against a building. The angle of elevation of the ladder is 70°. The top of the ladder is 25 ft from the ground. 

 To the nearest tenth of a foot, how far from the building is the base of the ladder? 
 (Points : 5)  
       20.5 ft
        30.5 ft
        32.3 ft
        39.5 ft

anonymous · Answer

Consider the base as x and the height 25.
So, as  x is the adjacent cathetus and 25, the opposite, you have to use the tangent formula.
Tan70=25/x