Answer:
(This means find the output of the functions when x = 4) Find x when f(x)=1 (This means find the input that gives an output of 1.) Found 2 solutions by Alan3354, ... John My calculator said it, I believe it, that settles it
Step-by-step explanation:
Answer:
8 and 9.
Step-by-step explanation:
Let the two unknown numbers be a and b.
When added together, they equal 17. In other words:
a + b = 17.
The <em>difference</em> between five times the first number and three times the second number is 13. In other words:
5a - 3b = 13.
We have a system of equations. We can use substitution. From the first equation, we can derive a = 17 - b. Let's substitute this in:
5(17 - b) - 3b = 13
85 - 5b - 3b = 13
-8b = -72
b = 9
a = 17 - b.
a = 17 - 9 = 8.
Thus, the two numbers are 8 and 9.
Answer:
70
Step-by-step explanation:
There are 8 choices for the first member, 7 for the second, 6 for the third, and 5 choices for the fourth member (because once you pick someone as a member, they cannot be picked again)
So you have:
8*7*6*5 = 1680
However, we realize that in this particular problem, order DOES NOT matter. (for example, ABCD is the same as DCBA.)
So we divide 1680 by 4! (4*3*2*1) to end up with 70.
You do this because because there are 4! ways to arrange 4 people in a line, and since order doesn't matter, only one of those arrangements counts.
The formula
a(n) = 2 - 5(n-1)
is in the form
a(n) = a1 + d(n-1)
where
a1 = first term = 2
d = -5 = common difference
The first term is carried over to the recursive formula. We start with a1 = 2. The next term after that is found by subtracting 5 from the previous term. So
second term = (first term) - 5
third term = (second term) - 5
and so on
The recursive step would be
a(n) = a(n-1)-5
So that's why the answer is choice C