we know that in direct variation as x increase y also increases.
in indirect variation x decreases y increase and vice versa.
in part a we have x at top (numerator ) and y at denominator it mean indirect variation (as x increases y decreases).
to find k we know that for indirect variation xy=k
if we rewrite the equation x=9/y we get xy=9
which mean k=9 .
in part b we have 4xy=20 if we simplify this equation we get
so here if we rewrite in terms of x.
we get x=5/y which represents indirect variation.
and we know xy=k
we have xy=5 .so k=5
0, 1/3, 2/3, 1, 1 1/3, 1 2/3, 2
Answer:
-2, 8/3
Step-by-step explanation:
You can consider the area to be that of a trapezoid with parallel bases f(a) and f(4), and width (4-a). The area of that trapezoid is ...
A = (1/2)(f(a) +f(4))(4 -a)
= (1/2)((3a -1) +(3·4 -1))(4 -a)
= (1/2)(3a +10)(4 -a)
We want this area to be 12, so we can substitute that value for A and solve for "a".
12 = (1/2)(3a +10)(4 -a)
24 = (3a +10)(4 -a) = -3a² +2a +40
3a² -2a -16 = 0 . . . . . . subtract the right side
(3a -8)(a +2) = 0 . . . . . factor
Values of "a" that make these factors zero are ...
a = 8/3, a = -2
The values of "a" that make the area under the curve equal to 12 are -2 and 8/3.
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<em>Alternate solution</em>
The attachment shows a solution using the numerical integration function of a graphing calculator. The area under the curve of function f(x) on the interval [a, 4] is the integral of f(x) on that interval. Perhaps confusingly, we have called that area f(a). As we have seen above, the area is a quadratic function of "a". I find it convenient to use a calculator's functions to solve problems like this where possible.
Answer:
$19.99 for each cartridge.
Step-by-step explanation:
For this problem, we are finding the cost of the three printer cartridges. Since the problem says that the tax was 5.95, we can subtract that from 90.91.
90.91-5.95=
84.96
Next, since we know that the software package was 24.99, we can subtract that from 84.96.
84.96-24.99=
59.97
Finally, since there are three printer cartridges, we can divide 59.97 by 3, and get our answer.
59.97/3=
19.99
Each printer cartridge would cost $19.99.
Hope this helps and have a good day! :D
Answer:
60 or 60:1
Step-by-step explanation:
You will have to divide 180 by 3 which is 60 or you can divide 160 / 3 = 60 & divide 3 / 3 = 1.