The answer for the question shown above is the second one, which is: The domain is all real numbers. The range is all real numbers greater than zero.
The explanation is shown below:
You have the following function given in the problem above f(x)= (1/5)^x. As you can see, it is a exponential function. By definition, the domain of the exponential functions is all the real numbers anf their range is all real numbers greater that zero.
What do you not understand?
Let,the time taken by larger pipe = x
By smaller pipe = x+5
It would be: 1/x + 1/(x+5) = 9/100
= x+5+x /(x)(x+5) = 9/100
= 2x+5 / x²+5x = 9/100
= 100(2x + 5) = 9(x² + 5x)
= 200x + 500 = 9x² + 45x
= 9x² - 155x - 500 = 0
= 9x² - 180x + 25x - 500 = 0
= 9x(x - 20) + 25(x - 20) = 0
= (9x + 25) (x - 20) = 0
= x = -25/9 or x = 20
Time can't be in negative so -25/9 is rejected.
Now,x + 5 = 20 + 5 = 25
In short, Your Larger pipe takes 20 minutes and smaller pipe takes 25 minutes
Hope this helps!
Multiply it for all of the area
Answer:
Step-by-step explanation:
Speed=distance×time
650×3=1950
Speed=1950miles/hour