Answer:
Step-by-step explanation:
Since there is no single number we can add to one number in the sequence to get to the next one, this is not arithmetic. That means it's geometric, if it's a sequence at all. To get from 2 to 6 we multiply by 3. To get from 6 to 18 we multiply by 3. To get from 18 to 54 we multiply by 3. Therefore, this is in fact geometric and the common ratio is 3. The standard form of a geometric explicit formula is
where n is the position of a number in the sequence, a1 is the first number in the sequence, and r is the common ratio. We have then
a1 = 2 and r = 3. Therefore, the explicit formula is
and you can use this to find the value of any number in the sequence. Very handy; much more so than the recursive formula, which requires that all the numbers in a sequence be found in order in order to get to a desired value.
Answer:
B
Step-by-step explanation:
Answer:
The number of nickel coins is 10 and the number of quarter coins is 5
Step-by-step explanation:
<u><em>The correct question is</em></u>
Mary has 15 coins with the total value of $1.75 if the coins are nickels and quarters how many of each kind are there
Let
x ----> the number of nickel coins
y ----> the number of quarter coins
Remember that


we know that
Mary has 15 coins
so
-----> equation A
The total value of the coins is $1.75
so
----> equation B
Solve the system by graphing
Remember that the solution is the intersection point both graphs
using a graphing tool
The solution is the point (10,5)
therefore
The number of nickel coins is 10 and the number of quarter coins is 5
Step-by-step explanation:
16x^2 - 4
4(4x²-1)
4((2x)²-1²)
4(2x+1)(2x-1)