X-y=-4 is the equation for question listed above, no direct variation.
Answer:
4555566
Step-by-step explanation:
Step-by-step explanation:
Answer:
$27.14
Step-by-step explanation:
Price of 1 DVD: $9.10
Price of 4 DVDs: 4 * $9.10 = $36.40
Discount: 25%
Now we find 25% of $36.40.
25% of $36.40 =
= 0.25 * $36.40
= $9.10
The 25% discount amounts to $9.10. We now subtract $9.10 from $36.40 to find the discounted price.
$36.40 - $9.10 = $27.30
Now we need to apply the 6.75% tax to $27.30.
6.75% of $27.30 =
= 0.0675 * $27.30
= $1.84
The sales tax is $1.84.
Now we add the sales tax amount to the total discounted price.
$27.30 + $1.84 = $29.14
Answer: $27.14
Answer:
f = xy²-2x² satisfies that F = ∇f.
Step-by-step explanation:
F(x,y) = (y² - 4x) i + 2xy j
We want f(x,y) such that
Lets find a primitive of y²-4x respect to the variable x. We need to think y (and y²) as constants here, so a primitive of y² would be xy² the same way that a primitive of k is xk (because we treat y² as constant). A primitive of x is x²/2, thus a primitive of 4x is 2x². Thus, a primitive of y²-4x is xy² - 2x². We can obtain any other primitive by summing a constant, however since we treated y as constant, then we have that
where c(y) only depends on y (thus, it is constant repsect with x).
We will derivate the expression in terms of y to obtain information about c(y)
Thus, is constant. We can take f(x,y) = xy²-2x². This function f satisfies that F = ∇f.