Question

An extension ladder leans against a burning fling, making a 75° angle of elevation with the ground. the base of the ladder is 8 ft from the base of the building. to the nearest tenth of a food how long is the ladder?

a) 10.1 ft
b) 16.3ft
c)29.9 ft
d)30.9 ft

Answer 1

For this case we can model the problem as a rectangle triangle.
We know:
Angle between the base of the triangle and the hypotenuse
Length of the base of the triangle
We want to know:
Length of the hypotenuse.
For this we use the following trigonometric relationship:

`cos (75) = 8 / h`
Clearing h we have:

`h = 8 / cos (75) h = 30.9 feet`
Answer:
the ladder is 30.9 feet long:
d) 30.9 ft