Answer:
<em>C(12)=$570.18</em>
<em>C(20)=$57.08</em>
Step-by-step explanation:
<u>Exponential Decay Function</u>
The exponential function is often used to model natural growing or decaying processes, where the change is proportional to the actual quantity.
An exponential decaying function is expressed as:

Where:
C(t) is the actual value of the function at time t
Co is the initial value of C at t=0
r is the decaying rate, expressed in decimal
The depreciation of goods is often modeled as an exponential function. The new car costs $18,000 and its price depreciates at r=25%= 0.25 every year.
The depreciation model is:

Operating:

At t=12 years, the price will be:

C(12)=$570.18
At t=20 years, the price will be:

C(20)=$57.08
Answer:
sometimes
Step-by-step explanation:
Discounted at 15% off....means the kid actually paid 85%
0.85(18) = 15.30
and then there is the 6% sales tax...
15.30 * 1.06 = 16.218 rounds to $ 16.22 <== what she pays
Answer:
A = 28 cm^2 (4+24)
B = 34 cm^2 (40-6)
C = 96 cm^2 (150-54)
D = 40 cm^2 (1/2(8*5) + 1/2(8+5))
Step-by-step explanation:
Answer:
A) x = − 1, y = 2, z = 3
Step-by-step explanation:
4x − 2y + 3z = 1
x + 3y − 4z = −7
3x + y +2z = 5
Lets eliminate x by multiplying the second equation by -4
4x − 2y + 3z = 1
-4x - 12y + 16z = 28
-----------------------------
-14y +19z = 29
Lets eliminate x by multiplying the second equation by -3
-3x + -9y +12z = 21
3x + y +2z = 5
---------------------------
-8y +14z =26
We now have 2 equations and 2 unknowns
-14y +19z = 29
-8y +14z = 26 Divide this by 2 = -4y +7z = 13
Multiplying the first equation by 4 and the second by -14
-56y +76z =116
56y -98z = -182
----------------------------
-22z =-66
Divide each side by -22
-22z/-22 = -66/-22
z=3
Now we need to find y
-14y +19z = 29
-14y +19(3) =29
-14y+ 57 = 29
-14y =29-57
-14y =-28
y =2
Now we need to find x
x + 3y − 4z = −7
x + 3(2) -4(3) =-7
x+6 -12 =-7
x-6 = -7
x = -1