Answer:
the second answer Is the right one
9514 1404 393
Answer:
B, D
Step-by-step explanation:
The quadratic expands to ...
(2n -1)² = (2n)² +2(2n)(-1) +(-1)² = 4n² -4n +1
The coefficients can be factored out of the sum, so ...
∑(4n²) = 4∑n² for example
The sum of 60 ones is 60:

So, the sum can be written as ...

_____
It appears that the key to choosing the correct answers is paying attention to signs.
Answer:
x = -3
y = -6
Step-by-step explanation:
x+y = -11
x-y = 5
x+y+x-y= -6
2x= -6
x = -3
y = -6
Hi there!
Thanks for asking for help!
I believe Part A of your answer is the expression: n+2n.
Because that is the answer for Part A, Part B is the answer: "The expression for the bookcases is n+2n because the problem says 'the larger bookcase holds twice as much as the smaller one,' and 'let n represent the amount of books the smaller bookcase holds'.
Since you need to find an expression for the amount both bookcases needs to hold you would add n (capacity of the smaller bookcase) and 2n (capacity of the larger bookcase) together to have an expression that represents the amount both hold.
Part C: 90=3n
I know this is the correct equation based on the expression written above since n+2n=3n, and the problem says "the amount both bookcases hold together is 90 books"
btw, bookcase 1 holds 30 books and the large bookcase holds 60.
Hope this helps you out! :)
Answer:
1 / 8568
Step-by-step explanation:
The number of combinations is:
₁₈C₅ = (18! / (5! (18−5)!)
₁₈C₅ = 8568
There are 8568 possible groups of 5 that can be selected from 18. Only 1 of those groups contains the five youngest students. So the probability is:
P = 1 / 8568 ≈ 0.0117%