Answer:

Step-by-step explanation:
Circumference is the perimeter of a circle. It can be found using the formula:

However, we are given the radius.
- The radius measures from the center to the edge of the circle.
- The diameter measures from edge to edge through the center.
- So, the diameter is twice the radius, or d=2r
The formula can be rewritten as:

We know the circumference is 25.12 inches.

Let's round pi to 3.14

We want to solve for the radius, so we must isolate it.
Divide both sides by 3.14 because the inverse of multiplication is division.


Divide both sides by 2.


The radius of the disc is <u>4 inches.</u>
Answer:
21. y = 75000·0.935^t
22. after 74.6 days
23. y = 27.8112·1.18832^t
24. 18.8% per month
25. 1748
Step-by-step explanation:
22. It is convenient to use the graphing calculator to solve this problem. The number of days is where the exponential curve has the value 500. It is about 74.55 days. (see the first attachment)
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23. y = 27.8112·1.18832^t (see the second attachment)
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24. The rate of change is the difference between the base of the exponential and 1, often expressed as a percentage. The time period is the units of t.
(1.18832 -1) × 100% ≈ 18.8% . . . . per month
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25. Evaluating the function for t=24 gives y ≈ 1748.30425259 ≈ 1748.
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<em>Comment on graphing calculator</em>
A graphing calculator can make very short work of problems like these. It is worthwhile to get to know how to use one well.
Width of the reactangle = 38 cm
Minimum perimeter = 692 cm
Let the length of the rectangle be x cm
We know that,
Perimeter of rectangle = 2 * (length + width)
Since the perimeter should be atleast 692 cm. Therefore,
2 * (x + 38) > 692
2x + 76 > 692
2x > 692 - 76
2x > 616
x > 
x > 308
Hence, the length of the rectangle should be more that 308 cms.
Answer:
GIVE ME MY RAMEN
Step-by-step explanation:
3.
add like terms
30 + 7k = 100
100-30 = 70
70 divided by 7k = 10
k = 10
4. add the z's together
2z - 6 -2 = -10
+ 6 + 2
-10 will be -2 now since we dragged the -6 and -2 to the other side
2z = -2
z = -1
5. 3.2x - 1.7x = 1.5x
1.5x + 5.5 = 10
10 would be 4.5 since we dragged 5.5 to the other side so it would be 10 - 5.5
3.2x = 5.5
x = 1.71875
6.
3/4x - 1/4x = 2/4x
14 - 3 = 11
2/4x = 11
x = 22
27 - 9x +15y
Factor out common term 3 :
3(9-3x+5y)
hope this helps!