Answer:
The distance between the two boats after 2.5 hours is 57 m.
Step-by-step explanation:
The distance covered by each boat after 2.5 hours are:
speed = 
distance = speed x time
For boat A, speed = 14 km/h and time = 2.5 hrs.
So that,
distance = 14 x 2.5
= 35 km
For boat B, speed = 18 km/h and time = 2.5 hrs.
So that,
distance = 18 x 2.5
= 45 km
The distance between the two boats after travelling 2.5 hours can be determined by applying the cosine rule. Let the distance be represented by x, so that:
= 
+ 
- 2bc Cos A
= 
+ 
- 2(45 x 35) Cos 
= 2025 + 1225 - 3150 (0)
= 3250
x = 
= 57.0088
x = 57.0 m
The distance between the two boats after 2.5 hours is 57 m.
<h3>
Answer: Approximately 6.58 years old</h3>
The more accurate value is 6.57881347896059, which you can round however you need. I picked two decimal places.
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Explanation:
Let's pick a starting value of the car. It doesn't matter what the starting value, but it might help make the problem easier. Let's say A = 1000. Half of that is 1000/2 = 500.
So we want to find out how long it takes for the car's value to go from $1000 to $500 if it depreciates 10% per year.
The value of r is r = 0.10 as its the decimal form of 10%
t is the unknown number of years we want to solve for
---------------------------
y = A(1 - r)^t
500 = 1000(1 - 0.1)^t
500 = 1000(0.9)^t
1000(0.9)^t = 500
0.9^t = 500/1000
0.9^t = 0.5
log( 0.9^t ) = log( 0.5 )
t*log( 0.9 ) = log( 0.5 )
t = log( 0.5 )/log( 0.9 )
t = 6.57881347896059
Note the use of logs to help us isolate the exponent.
Addition of a positive and negative number always means that you are going to subtract the number e. g. 4+-1 = 3. However, multiplication of a positive and negative number means the answer is always negative e. g. 5 x - 3 = - 15.
The answer is x=5 do u need steps?
