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Liono4ka [1.6K]

3 years ago

12

About 79,000 people live in a circular region with a population density of about 513 people per square mile. Find the radius of

the region. Round your answer to the nearest whole number.

1 answer:

Natalija [7]3 years ago

5 0

To solve this problem, let us first assign some variables. Let us say that:

d = represents the population density of the circular region (in units of 513 people per square mile)

p = represents the population of the circular region (in units of people)

r = is the radius of the circular region

Now we can see that if we divide p by d, we can get a value which has a units of square mile. Thus the area of the region, hence:

Area = 79,000 people / (513 people per square mile)

Area = 154 square mile

The area of a circle has the formula:

Area = π r^2

Therefore calculating for r:

154 square mile = π r^2

r = 7 miles (ANSWER)

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You buy a house for $230,000. It depreciates 3% per year. How much is it worth in 5 years?

Nookie1986 [14]

I honestly don’t know the equation but I just took the starting price, $230,000 and multipled it by .03 which was 6,900 and subtracted that from 230,000: 223,190. I repeated that 5 times. The answer I got is 197,508.83

3 0

2 years ago

Pls show work! questions on pic

Lena [83]

Answer:

a.(10,23)

b.(7,30)

e.(20,20)

Step-by-step explanation:

We are given that

x=Width of garden

y=Length of garden

According to question

$x\geq 5$

$y\geq 20$

Perimeter of rectangle= $2(x+y)$

Where x=Width of rectangle

y=Length of rectangle

Fencing used = $2(x+y)$

$2(x+y)\leq 80$

First we change inequality into equality

$x=5$ ...(1)

$y=20$ ...(2)

$2(x+y)=80$

$x+y=40$ ...(3)

Substitute x=0 in equation (3)

$y=40$

Substitute y=0 in equation (3)

$x=40$

Substitute x=0 and y=0 in equation (3)

$2(x+y)\leq 80$

$0\leq 80$

It is true. Therefore, the shaded region below the line.

$0\geq 5$

$0\geq 20$

These are false equation .Therefore, the shaded region above the line.

Substitute x=5 in equation (3)

$5+y=40$

$y=40-5=35$

Substitute y=20 in equation (3)

$x+20=40$

$x=40-20=20$

Intersection point of equation (1) and (3) is (5,35) and intersect point of equation (2) and (3) is (20,20).

Now,

a.(10,23)

Substitute in

$2(x+y)\leq 80$

$2(10+23)\leq 80$

$66\geq 80$

10>5 and 23>20

it satisfied all inequality.

Hence, it is a solution.

b.(7,30)

7>5

30>20

$2(7+30)=74$

it satisfied all inequality.

Hence, it is a solution.

c.(18,25)

18>5

25>20

$2(18+25)=86>80$

It does not satisfied third inequality

Hence, it is not a solution.

d.(8,35)

8>5

35>20

$2(8+35)=86>80$

It does not satisfied third inequality

Hence, it is not a solution.

e.(20,20)

$2(20+20)=80$

20>5

20=20

it satisfied all inequality.

Hence, it is a solution.

4 0

3 years ago

We have a jar of coins, all pennies and dimes. All together, we have 309 coins, and the total value of all coins in the jar is $

Vinvika [58]

There are 130 pennies in the jar

Step-by-step explanation:

We have a jar of coins

All coins are pennies and dimes
There are 309 coins in the jar
The total value of all coins in the jar is $ 19.2

We need to find the number of pennies in the jar

Assume that there are p pennies and d dimes in the jar

∵ There are p pennies and d dimes in the jar

∵ There are 309 coins in the jar

∵ All the coins in the jar are pennies and dimes

∴ p + d = 309 ⇒ (1)

∵ The total value of all coins in the jar is $ 19.2

∵ $1 = 100 cents

∴ $19.2 = 19.2 × 100 = 1920 cents

∵ 1 penny = 1 cent

∵ 1 dime = 10 cents

∴ p + 10 d = 1920 ⇒ (2)

Now we have system of equations, we can solve them to find p

∵ p + d = 309 ⇒ (1)

∵ p + 10 d = 1920 ⇒ (2)

- Multiply equation (1) by -10 to eliminate d

∵ (-10)(p) + (-10)(d) = (-10)(309)

∴ -10 p - 10 d = -3090 ⇒ (3)

Add equations (2) , (3)

∴ -9 p = -1170

- Divide both sides by -9

∴ p = 130

There are 130 pennies in the jar

Learn more:

You can learn more about the system of equations in brainly.com/question/3739260

#LearnwithBrainly

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3 years ago

Factorise each of the following algebraic expressions completely,

LekaFEV [45]

Answer:

see explanation

Step-by-step explanation:

(a)

Given

2k - 6k² + 4k³ ← factor out 2k from each term

= 2k(1 - 3k + 2k²)

To factor the quadratic

Consider the factors of the product of the constant term ( 1) and the coefficient of the k² term (+ 2) which sum to give the coefficient of the k- term (- 3)

The factors are - 1 and - 2

Use these factors to split the k- term

1 - k - 2k + 2k² ( factor the first/second and third/fourth terms )

1(1 - k) - 2k(1 - k) ← factor out (1 - k) from each term

= (1 - k)(1 - 2k)

1 - 3k + 2k² = (1 - k)(1 - 2k) and

2k - 6k² + 4k³ = 2k(1 - k)(1 - 2k)

(b)

Given

2ax - 4ay + 3bx - 6by ( factor the first/second and third/fourth terms )

= 2a(x - 2y) + 3b(x - 2y) ← factor out (x - 2y) from each term

= (x - 2y)(2a + 3b)

8 0

3 years ago

4 3. Brodie has a bag of mixed fruit snacks. In the bag, there are 8 cherry fruit snacks and 12 strawberry fruit snacks. What is

Greeley [361]

Answer: simplified ratio would be 3:2

Step-by-step explanation: the ratio would be 12:8

5 0

3 years ago

Read 2 more answers