In calculus, we use derivatives to find the instantaneous rate of change at any point on a graph. To find the average rate of change, we just find the slope of the secant line that intercepts two points on the graph.
We find slope with the following equation:

In this case, we are looking for the slope from x = -1 to x = 1. We have both x values, so next we need the y values.
F(-1) = (-1)^2 - (-1) - 1 = 1
F(1) = (1)^2 - (1) - 1 = -1
Now plug in the x and y values to find the slope:
The answer is -1.
2x + 9 = 35
We subtract 9 in both sides:
2x + 9 - 9 = 35 - 9
2x = 26
We then divide 2 in both sides:
x = 13
C. "David's equation is correct, because their spending will be multiplied by the number of months and then subtracted from their savings"
they are technically saying "Look we have 12,350 to use. How long (y) will the savings (12,350) last after using 240 each month (x)
so the amount they use *PER* month gets subtracted from the savings because they are using that money to pay with
Hope this helps :)
9514 1404 393
Answer:
$13,916.24
Step-by-step explanation:
First, we need to find the value of the CD at maturity.
A = P(1 +rt) . . . . simple interest rate r for t years
A = $2500(1 +0.085·3) = $2500×1.255 = $3137.50
__
Now, we can find the value of the account with compound interest.
A = P(1 +r)^t . . . . . rate r compounded annually for t years
A = $3137.50 × 1.18^9 = $13,916.24
The mutual fund was worth $13,916.24 after 9 years.