Trigonometry help

Question

If you can please click on the link below and help me out with one problem for my geometry class in which i am learning a lesson in trigonometry, thank you so much in advance.

http://s1039.photobucket.com/user/dani_doll98/media/IMG_2158_zps4ew9xrzv.jpg.html?sort=3&o=0

Answer 1

(a)

The bottom of the plank is from the wall.

A wooden plank is leaning against a wall.

Consider .

Draw the related diagram:

Observe the diagram:

.

The length of the plank is .

Answer 2

(b)

From the diagram in part (a):

.

The height off the ground where board touches the wall is .