Answer:
c. ½x + 4 = 12; x = 16
Step-by-step explanation:
1/2 x ( Half of the allowance spent at movies & x is allowance )
1/2x + 4 ( Earned additional $4 )
1/2x + 4 = 12 ( Had $12 at the end of the week )
Check:
1/2 16 +4 = 12
8 + 4 = 12
12 = 12
Correct!
Answer:
The fourth term of the expansion is -220 * x^9 * y^3
Step-by-step explanation:
Question:
Find the fourth term in (x-y)^12
Solution:
Notation: "n choose k", or combination of k objects from n objects,
C(n,k) = n! / ( k! (n-k)! )
For example, C(12,4) = 12! / (4! 8!) = 495
Using the binomial expansion formula
(a+b)^n
= C(n,0)a^n + C(n,1)a^(n-1)b + C(n,2)a^(n-2)b^2 + C(n,3)a^(n-3)b^3 + C(n,4)a^(n-4)b^4 +....+C(n,n)b^n
For (x-y)^12, n=12, k=3, a=x, b=-y, and the fourth term is
C(n,3)a^(n-3)b^3
=C(12,3) * x^(12-3) * (-y)^(3)
= 220*x^9*(-y)^3
= -220 * x^9 * y^3
12/20 can be simplified to 3/5
Answer:
Step-by-step explanation:
It means the higher the price is per wash, the lower the number of expected customers is.