You can choose from 20 students for the first student, 19 for the second, 18 for the third, ..., 14 for the seventh student.
That gives you 20 * 19 * 18 * 17 * 16 * 15 * 14.
That number would allow you to write the students in different order. Since order here does not matter, any group with the same students in any order is the same group, you need to divide by the number of way you can order 7 items. Divide by 7 * 6 * 5 * 4 * 3 * 2 * 1
(20 * 19 * 18 * 17 * 16 * 15 * 14)/(7 * 6 * 5 * 4 * 3 * 2 * 1) = 77,520
Answer: 77,520
I'm assuming all of (x^2+9) is in the denominator. If that assumption is correct, then,
One possible answer is 
Another possible answer is 
There are many ways to do this. The idea is that when we have f( g(x) ), we basically replace every x in f(x) with g(x)
So in the first example above, we would have

In that third step, g(x) was replaced with x^2+9 since g(x) = x^2+9.
Similar steps will happen with the second example as well (when g(x) = x^2)
Answer:
Therefore the results from adding the equation in this system is

Step-by-step explanation:
Given:
Equations as
.......................1
.......................2
To Find :
Result when adding equation 1 and 2 = ?
Solution
On adding equation 1 and 2 the "3y" term will get cancel and the like terms will combine that is add (11x and -4x ) and ( -17 and - 18) as shown below
11x - 3y = -17
-4x + 3y = - 18
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7x + 0 = - 35
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Therefore the results from adding the equation in this system is

Answer:
3)7
Step-by-step explanation:
Answer:
l=24in
Step-by-step explanation:
P=2(l+w)
l=P
2﹣w=68
2﹣10=24in