Answer:
The correct option is;
False
Step-by-step explanation:
The coefficient of x^k·y^(n-k) is nk, False
The kth coefficient of the binomial expansion, (x + y)ⁿ is 
Where;
k = r - 1
r = The term in the series
For an example the expansion of (x + y)⁵, we have;
(x + y)⁵ = x⁵ + 5·x⁴·y + 10·x³·y² + 10·x²·y³ + 5·x·y⁴ + y⁵
The third term, (k = 3) coefficient is 10 while n×k = 3×5 = 15
Therefore, the coefficient of x^k·y^(n-k) for the expansion (x + y)ⁿ = 
not nk
Answer:
Step-by-step explanation:
It can end with a 0.
For example 12 * 5 = 60.
49 is composite because it has factors other than itself and 1, 7 and 7, namely. So you could have one row of 49 books, 49 rows of one book or 7 rows of 7 books.
Let x be the first number and y be the second.
2x + y = 25
3x - y =20
1) Add them together.
5x = 45
x = 9
2) Solve for y.
2(9) + y = 25
y=7
3) Check your work on the other equation.
3(9) - (7) = 20
27 - 7 =20
20 = 20
Add them all up then divide by 5, so it should be 666.43
