^{0}with the ground. The foot of the ladder is 3.5 m away from the wall. Find the length of the ladder.

^{0}=

^{AB}/

_{AC}

_{}

^{1}/

_{2 }=

^{3.5}/

_{AC}

A ladder leaning against a vertical wall, makes an angle of 60^{0} with the ground. The foot of the ladder is 3.5 m away from the wall. Find the length of the ladder.

Solution:

Let AC be
the length of the ladder,

AB be the
distance between the foot of the ladder and the base of the wall.

Thus, AB =
3.5 m (Given)

In right
angled triangle, ∆ ABC,

cos 60^{0} = ^{AB}/_{AC}

∴^{1}/_{2 }= ^{3.5}/_{AC}

∴ AC = 3.5 × 2

∴ AC = 7 m.

∴ The length of the ladder is 7m.