A 13.5 -m fire truck ladder is leaning against a wall. Find the distance d the ladder goes up the wall (above the fire truck) if the ladder makes an angle of 39 degrees 45 ' with the horizontal.

Solution

Assuming the ladder makes a right triangle with the wall, length of the ladder will be the hypotenuse (13.5m)

find the height

sin39.75 = opposite/13.5m

= 0.6394 * 13.5m

=8.63m

To solve this problem you must apply the proccedure shown below:

1. You have the the 13.5 -m fire truck ladder is leaning against a wall and the ladder makes an angle of 39 degrees 45 ' with the horizontal.

2. Then you have:

3 9 degrees 45'=39.75°

Sin (39.75°) = d/13.5

d=13.5x Sin (39.75°)

d=8.63