Answer: The average rate of change of Jack's investment from the third year to the fifth year is $6.43
Step-by-step explanation:
The function that defines the value of his investment after x years,
Putting the value of x as 3 and 5, we can get the value of his investment after 3 years and 5 years respectively.

It's clear that for x not equal to 4 this function is continuous. So the only question is what happens at 4.
<span>A function, f, is continuous at x = 4 if
</span><span>

</span><span>In notation we write respectively
</span>

Now the second of these is easy, because for x > 4, f(x) = cx + 20. Hence limit as x --> 4+ (i.e., from above, from the right) of f(x) is just <span>4c + 20.
</span>
On the other hand, for x < 4, f(x) = x^2 - c^2. Hence

Thus these two limits, the one from above and below are equal if and only if
4c + 20 = 16 - c²<span>
Or in other words, the limit as x --> 4 of f(x) exists if and only if
4c + 20 = 16 - c</span>²

That is to say, if c = -2, f(x) is continuous at x = 4.
Because f is continuous for all over values of x, it now follows that f is continuous for all real nubmers 
3, 217
Sorry if it’s wrong
Hope this helped *smiles*
Answer:
10 meters.
Step-by-step explanation:
The area of a rectangle formula is width multiplied by length. So, to find the length of the pool, simply divide the width from the area.
90/9=10
The length of the pool is 10 meters.
Hope this helps!
If not, I am sorry.
Answer:

Step-by-step explanation:
The surface area of the prism consists of four rectangles and two trapezoids. The sum of the areas of these polygons will give the total surface area of the prism:
Rectangle 1 (top base): 
Rectangle 2 (bottom base): 
Trapezoids 1 and 2 (lateral): 
Rectangles 3 and 4 (lateral): 
Thus the total surface area is equal to