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.
Answer:
B. 20
Step-by-step explanation:
x + 40 = 3x
x - x + 40 = 3x - x
40 = 2x
20 = x
Using the context surrounding the word trough in line 9 of "Concrete Mixers," explain what a trough looks like and what it does on a concrete mixer. .
sorry I can't delete it this not answer your question
Use subtitution method to solve the problem.
First, change y to the value of x in order to find the exact value of x.
x + y = 4
y = 4 - x
Second, subtitute y with 4 - x from the first equation
y = -x² + 2x + 4
4 - x = -x² + 2x + 4
move all terms to the left side
x² - 2x - x + 4 - 4 = 0
x² - 3x = 0
x(x - 3) = 0
x = 0 or x = 3
Third, now we have 2 values of x. Find the value of y for each of x
For x = 0
y = 4 - x
y = 4 - 0
y = 4
For x = 3
y = 4 - x
y = 4 - 3
y = 1
The solution is (0,4) and (3,1). The answer is option b
