Answer: 1.58 hours
<u>Step-by-step explanation:</u>

D), I believe it is -42. Correct me if im wrong :}
Step-by-step explanation:
the average change rate of a function f(x) in an interval [x1 .. x2] is
(f(x2) - f(x1)) / (x2 - x1)
in our case that is
(7000 - 2500) / (20 - 0) = 4500 / 20 = 225
the population changed in average by 225 people per year from 1900 to 1920.
Answer:

Step-by-step explanation:
The equation to solve is:

To get rid of the "square", we need to take square root of both sides:

Then we use algebra to find the value(s) of x. Remember, when we take square root, we have to add up a "+-" (on the right side). Shown below:

So these are 2 answers for x.