Mathematics

A ladder 9m long leans against a vertical wall, making an angle of 64° with the…

A ladder 9m long leans against a vertical wall, making an angle of 64° with the horizontal ground. calculate correct to one decimal place, how far the foot of the ladder is from the wall.

  • A.
    4.0m
  • B.
    5.8m
  • C.
    7.1m
  • D.
    8.1m
  • E.
    18.5m
Correct Answer: Option A
Explanation

cos 64° = x/9x = 9 cos 64°
=3.94 ≅ 4.0m