9514 1404 393
Answer:
240
Step-by-step explanation:
The generic k-th term of the expansion of the binomial ...
(a +b)^n
is given by ...
(nCk)a^(n-k)b^k . . . . . where nCk = n!/(k!(n-k)!) and 0 ≤ k ≤ n
For this problem, we have ...
a=2x, b=y, n=6, k=2
Then the 2nd term (counting from 0) is ...
6C2×(2x)^4×y^2 = (6·5)/(2·1)·16x^4·y^2
= 240x^4y^2
The desired coefficient is 240.
_____
<em>Additional comment</em>
The coefficients for the expansion match the numbers in a row of Pascal's triangle. The row beginning with 1, n will have the coefficients for the expansion to the n-th power.
56 pages/4 hours = 126 pages/x pages
Then you cross multiply
56*x =4*126 ---> 56x=504
Then you divide 56 to both sides
56x/56=504/56
The 56 cancels on the left side and then you get
x=9
So your proportion are:
56 pages/4hours=126 pages/9 hours
I believe you are describing a vertex