18 choose 7
=C(18,7)
=18!/(7!(18-7)!)
=31824
OR
18 choices for first passenger,
17 choices for second passenger,
....
12 choices for 7th passenger,
so total = 18*17*16...12
but there are 7! ways to order the 7 passengers, so
number of groups
=18*17*16...12/7!
=31824 as well
Add 1 to both sides:

In cases like this, we have to remember that a root is always positive, so we can square both sides only assuming that

Under this assumption, we square both sides and we have

The solutions to this equation are

But since we can only accept solutions greater than -1, we discard
and accept
.
In fact, we have

and

which is the only solution.
Answer:
the answer is y=2x+8
Step-by-step explanation:
The equation that models the exponential decline is y = 46348587109809610(0.9861)ˣ if the population over the past 20 years is provided.
<h3>What is the line of best fit?</h3>
A mathematical notion called the line of the best fit connects points spread throughout a graph. It's a type of linear regression that uses scatter data to figure out the best way to define the dots' relationship.
Let's suppose the equation that models the exponential decline is:

From the data given, we can calculate the value of a and b:
a = 46348587109809610
b = 0.9861
y = 46348587109809610(0.9861)ˣ
Thus, the equation that models the exponential decline is y = 46348587109809610(0.9861)ˣ if the population over the past 20 years is provided.
Learn more about the line of best fit here:
brainly.com/question/14279419
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