Question

Set up a right triangle model for this problem and solve by using a calculator. Follow the models above,

Answer 1

Question:

Set up a right triangle model for this problem and solve by using a calculator. Follow the models above,

A photographer stands 60 yards from the base of a lighthouse and observes that the angle between the  ground and the top of the lighthouse is 41° How tall is the lighthouse?

Answer:

The height of lighthouse is 52.2 yards

Solution:

Given that photographer stands 60 yards from the base of a lighthouse and observes that the angle between the  ground and the top of the lighthouse is 41 degree

The diagram is attached below

Consider a right angled triangle ABC

AB is the height of the lighthouse

BC is the distance between the base of a lighthouse and Photographer

As per given, BC = 60 yards

Angle between the  ground and the top of the lighthouse is 41 degree

Angle ACB = 41 degree

To find: height of lighthouse i.e AB = ?

We know that,

$tan(\angle ACB) = \frac{Perpendicular}{Base}$

Here Base is BC and perpendicular is AB

$\tan 41^{\circ}=\frac{A B}{B C}$

Substituting the values,

$\begin{aligned}&\tan 41^{\circ}=\frac{A B}{60}\\\\&0.8692=\frac{A B}{60}\\\\&A B=0.8692 \times 60=52.157 \approx 52.2\end{aligned}$

Thus the height of lighthouse is 52.2 yards