A log is seen floating down a river. The log is first spotted 45 feet away. 7 minutes later the log is 10 feet away, making a 60° angle
between the two sightings. How far did the log travel? Round to the nearest tenth.
Answer



Answer :

Answer:

Step-by-step explanation: determine how far the log traveled, we can use the Law of Cosines. This law allows us to find the length of one side of a triangle when we know the lengths of the other two sides and the included angle.

Given:

The first distance from the spotter to the log is a=45 feet.

The second distance from the spotter to the log is b=10 feet.

The angle between these two sightings is θ=60

.

The Law of Cosines is given by:

c

2

=a

2

+b

2

−2abcos(θ)

where c is the distance the log traveled, which we need to find.

Plugging in the given values:

a=45 feet

b=10 feet

θ=60

 (which we convert to radians as cos function in most calculators and programming languages uses radians)

Let's compute c using this formula