Question

Help pre-algebra PLEASE!

Answer 1

I need to get the answers and I don't know how to do these at all, please help me out

Answer 2

There are more but I just wanna be able to do these

Answer 3

For the field shaped like a capsule, the area of the rectangle portion is length * width. since you have 2 semi-circles, they make 1 whole circle. The area of a circle is pi*(r^2). Calculate the 2 areas, add them up, and you got it.

Answer 4

pi = 3.14 right ?

Answer 5

I don't know what R is

Answer 6

For 7. "Find the exact area of the circle", when most texts & teachers say "exact" they are stating that do not want an irrational number. In other words, the answer has to be an integer, a fraction (simplified), and/or symbols, in this case pi. So the "Exact Answer" would be 81pi.

Answer 7

I'm confused, what question are you on?

Answer 8

ok
nvm

Answer 9

R is the radius of a circle. Any line touching 2 points on a circle is called a Cord. A Cord that passes through the center of a circle is called a Diameter. Half of the diameter is called the Radius.

Answer 10

7

Answer 11

so 9 is the radius ?

Answer 12

I think the answer to your post, "What question are you on?" was the "How much does it cost to fertilize the filed which is a rectangle with 2 semi-circles.

Answer 13

right

Answer 14

How do I do that?

Answer 15

Yes, for question 7, the radius is 9. 9^2=81. The "exact area" of the circle would then be 81pi.

Answer 16

How do you do what?

Answer 17

the "How much does it cost to fertilize the filed which is a rectangle with 2 semi-circles.

Answer 18

question

Answer 19

what is 9. 9 ? what is the "." for ?

Answer 20

OK. from the jpg you attached, the question is numbered 9. That question shows a field with a rectangle and a semi-circle at each end.

Answer 21

The length of the rectangle is 105 yards and the width is 45 yards.

Answer 22

The area of the rectangle portion of the field is 105 * 45.

Answer 23

The 45 yard width of the field is also the diameter of the semi-circles.

Answer 24

The 2 semi-cricles make up 1 whole circle.

Answer 25

The radius of which is 45/2.

Answer 26

Take that radius, square it, and multiply it by the approximate value of pi (P) of 3.14.

Answer 27

Does that clear up the confusion?

Answer 28

Let me know if you are good with problems 7 & 9. Then we can tackle problem 6.

Answer 29

wait so 105 x 45 = the rectangle?

Answer 30

Yes. The area of a parallelogram is the length * the width. In this case, 105 yards * 45 yards.

Answer 31

Sorry for the delay. I just signed up and had to verify before continuing.

Answer 32

no problem :)

Answer 33

So, here is how you calculate the cost of fertilizing the field pictured.
Area of rectangle = 105yd * 45yd.
Area of the 2 semicircles = ((45/2)^2) * pi (3.14)
Add the 2 total areas.
Multiply the sum by $0.14/yd and you have your answer.

Answer 34

You good?

Answer 35

Now for problem 6, in case you come back later.

Answer 36

ok
4725 is the rectangle on 9 ?

Answer 37

Yes, 4,725 yd^2 is the area of the rectangle.

Answer 38

and the circle ?

Answer 39

First find the radius of the circle. 45yd/2

Answer 40

45 divided by 2 ?

Answer 41

Yes.

Answer 42

25 is the radius

Answer 43

No. It would be 25yd if the diameter was 50yd.

Answer 44

45yd divided by 2 = 22.5yd

Answer 45

right

Answer 46

\[22.5yd ^{2}=?\]

Answer 47

my bad kinda cant think right now so i made mistake like that

Answer 48

hmm

Answer 49

No problem.

Answer 50

As a professor, I rarely give the answer as it does not help the student when presented with a similar problem later.

Answer 51

Rather, I prefer to teach the student the process. If you understand the process, than the numbers don't really matter! They simply give you different answers using the same process.

Answer 52

yea
Understood :)

Answer 53

I have a test with answers like this and I have problems with it therefor I just wanna learn it so I can get it done with

Answer 54

OK. It will be much easier to learn the "formulas" for thew areas of different shapes.

Answer 55

so the circle to find that what have I to do ? (on 9)

Answer 56

we now that 45/2 = 22.5 now what

Answer 57

For 9, the area of a circle is, \[\pi*(radius ^{2}\)]

Answer 58

ok, 22.5 x 3.14 correct ?

Answer 59

\[\pi * (radius ^{2})\]

Answer 60

Do the radius squared 1st.

Answer 61

oh 45

Answer 62

\[9^{2}=81\]

Answer 63

no wait

Answer 64

506.25?

Answer 65

81 * 3.14 = 254.34

Answer 66

wait im confused on that Radius scared part

Answer 67

Where did that 506.25 come from?

Answer 68

22.5^2 = 22.5 x 22.5 = 506.25 correct ?

Answer 69

Make sure you always follow the order of operations.
Parenthesis, Exponents, Multiplication & Division, then Addition & Subtraction.

Answer 70

right, Please excuse my dear aunt sally

Answer 71

Yes, sorry about that. I was still back on the fertilizing the filed question.

Answer 72

ah

Answer 73

im on that one too lol

Answer 74

Lets start over, How do I do the circle part on the question 9, we now the rectangle what about the circle?

Answer 75

Now for the area of the circle, problem 7. To give the exact answer, you simply put pi after the numbers.
\[506.25\]

Answer 76

It did not post correctly. 506.25 pi (use the symbol in your answer).

Answer 77

ok

Answer 78

ok lets do seven real quick

Answer 79

I need to stop posting on 5 different problems simultaneously!

Answer 80

Back to problem 9 (the field needs fertilizing).

Answer 81

you said something like 9, 9^2
what is the period thing mean is it suppose to be times or ?

Answer 82

lol

Answer 83

lets do 7 first please :D

Answer 84

4725yd + (506.25*3.14) = 4725 + 1589.625yd = 6314.625yd.

Answer 85

Fertilizing cost $0.14 / square yard.

Answer 86

6314.625 * 0.14 = $884.0475. Round that to the nearest cent and you have a total cost of $884.05.

Answer 87

wait 506.25 * 3,14 = 3178.465

Answer 88

No, 506.25yd * 3.14 = 1589.625yd

Answer 89

right my bad

Answer 90

calculator error

Answer 91

To sum up how to solve a problem like #9,
Find the areas first. This is a "compound shape". 1 rectangle with 2 semi-circles.

The area of the rectangular portion is length * width. In this case 105yd * 45yd.

Since the 2 semi-circles have the same diameter, we simply divide the diameter by 2, then square that answer, lastly multiply that result by 3.14, the approximation you were instructed to use for pi.

Now you add your 2 areas. The total formula for this is:
\[(105yd*45yd) + ((45yd/2)^{2} * \pi)\]

Now take to total area, in this case \[yd ^{2}\], multiply by the cost per \[yd ^{2}\], and you have your total.

Answer 92

45/2 = 22.5

R = 22.5^2 = 506.25

Answer 93

506.25 x pi (3.14) = 1589.625

Answer 94

1589.625 + 4,725

Answer 95

right ?

Answer 96

\[(105yd * 45yd) = 4725yd ^{2}\]
\[((45yd/2)^{2} = 506.25piyd ^{2} = (505.25 * 3.14) = 1589.625yd ^{2}\]
\[4725yd ^{2} + 1589.625yd ^{2} = 6164.625yd ^{2}\]
\[6164.625yd ^{2} * $0.14/yd = $863.0425, round \to $863.05.\]