Question

A ladder 15 feet long leans against a house and makes an angle

of 60° with the ground. Find the distance from the house to the
foot of the ladder.
A 13 feet
)
B 7.5 feet
C 10 feet
D
8.2 feet

Answer 1

B

Explanation:

assume a right angle between the house and the ground.

then the ladder is the hypotenuse and distance from ladder to house is d

using the cosine ratio in the right triangle and the exact value

cos60° =
`(1)/(2)` , then

cos60° =
`(adjacent)/(hypotenuse)` =
`(d)/(15)` =
`(1)/(2)` ( cross- multiply )

2x = 15 ( divide both sides by 2 )

x = 7.5

distance from house to foot of ladder is 7.5 feet