I think I just had a stroke trying to read this
First, we inspect what type of sequence is the order of the coordinates:
a2 = 1
a3 = 2
a4 = 4
Getting the difference,
a3 - a2 = 1
a4 - a3 = 2
The differences are not equal; hence, the sequence is not arithmetic.
Getting the ratio:
a3/a2 = 2
a4/a3 = 2
The common ratio is 2. Using the general form for a geometric series:
an = a1 r^(n-1)
If n = 2
1 = a1 (2)^(2-1)
a1 = 1/2
So,
an = (1/2) (2)^(n-1)
The answer is the first option.
We will get the number of possible selections, and then subtract the number less than 25 cents.
We can choose the number of dimes 5 ways 0,1,2,3 or 4.
We can choose the number of nickels 4 ways 0,1,2 or 3.
We can choose the number of quarters 3 ways 0,1, or 2.
That's 5*4*3 = 60 selections
Now we must subtract from the 60 the number of selections of coins that are less than 25 cents. These will involve only dimes and nickels.
To get a selection of coin worth less than 25 cents:
If we use no dimes, we can use 0,1,2 on all 3 nickels.
That's 4 selections less than 25 cents. (that includes the choice of No coins at all in the 60, which we must subtract).
If we use exactly 1 dime , we can use 0,1,2, or all 3 nickels.
That's the 3 combinations less than 25 cents.
And there is 1 other selection less than 25 cents, 2 dimes and no nickels.
So that's 4+3+1 = 8 selections which we must subtract from the 60.
Answer 60-8 = 52 selections of coins worth 25 cents or more.
The answer should be D
Step by Step: |2x-2| <(or equal to) 6
Add 2 on both sides should give you, |2x| < 8
Divide both sides by 2, giving you 4
Other way, is doing the same but -2
7x+2=5(x-2)
7x+2=5x-10
7x-5x=-10-2
2x=-12
x=-6
Regards M.Y.
