Answer:
Step-by-step explanation:
Y is directly proportional to x, and y =216 when x=2 find y when x=7
1 answer:
You might be interested in
Answer:
a. Decay
b. 0.5
c. 4
Explanation:
If we have a function of the form
then
a = intital amount
b = growth / decay rate factor
x = time interval
If b > 1; then the equation is modelling growth. If b < 0, then the equation is modelling decay.
Now in our case, we have
Here we see that
inital amount = a = 4
b = 1/ 2 < 0, meaning the function is modeling decay
decay factor = b = 1/2
Therefore, the answers are
a. Decay
b. 0.5
c. 4
You can see how the difference between two consecutive terms is constantly increasing:
So, for the next terms we'll have to add +9, +11, +13 and so on.
Also, note that is obtained by adding the 2nd odd number to
,
is obtained by adding the 3rd odd number to
, and so on.
So, the recursive formula is
For the explicit formula, recall that the sum of the first n odd numbers is n squared. Taking into account the fact that we're not starting from 1, we have