All categories

3 years ago

Please help

1 answer:

katrin2010 [14]3 years ago

7 0

$\dfrac{n^2+3n+2}{n^2+6n+8}-\dfrac{2n}{n+4}\\\\=\dfrac{n^2+2n+n+2}{n^2+4n+2n+8}-\dfrac{2n}{n+4}\\\\=\dfrac{n(n+2)+1(n+2)}{n(n+4)+2(n+4)}-\dfrac{2n}{n+4}\\\\=\dfrac{(n+2)(n+1)}{(n+2)(n+4)}-\dfrac{2n}{n+4}\\\\=\dfrac{n+1}{n+4}-\dfrac{2n}{n+4}=\dfrac{n+1-2n}{n+4}=\dfrac{1-n}{n+4}$

$Answer:\ \boxed{B.\ \dfrac{1-n}{n+4}}$

You might be interested in

Can someone please help me I can’t figure this out!!

mixas84 [53]

1. Declarative
2. Interrogative
3. Imperative
4. Interrogative
5. Exclamatory? (Not 100% sure)
6. Exclamatory
7. Declarative
8. Imperative
9. Interrogative
10. Declarative

6 0

3 years ago

30 men repair a road in 56 days by working 6 hours daily. in how many days 45 men will repair same road by working 7 hours daily

zepelin [54]

Answer:

Case1:

Men : 30

Work : 1

Time (day×hr): 56×6 = 336 hr.

Case2:

Men : let it be m men.

Work: 1

Time: 45×7 = 315 hr.

Work being constant in both cases, men and time are in inverse proportion i.e, more men take less time.

Product of men and time is constant in both cases.

Therefore, 30×336=m×315

Or, 30×336/315 = m

Or, m = 32.

Hence, required number of men is 32.

Step-by-step explanation:

8 0

3 years ago

In the center of town there is a square park with an area of 900 square feet. If Stephen walks from one corner of the park to th

Vedmedyk [2.9K]

The distance walked by Stephen is 42.42 feet

<h3>Solution:</h3>

Given that In the center of town there is a square park with an area of 900 square feet

Stephen walks from one corner of the park to the opposite corner

To find: Distance walked by Stephen

We need to find the distance that the person walk from one corner of the park to the opposite corner.

So, we need to find the Diagonal of the square park

The diagonal of square is given as:

$\text{ Diagonal } = \sqrt{2} \times \text{ side}$

Let us find the length of side of square

Given area of square = 900 square feet

The area of square is given as:

$area = (side)^2\\\\900 = (side)^2$

Taking square root on both sides,

$side = \sqrt{900} \\\\side = 30$

Thus length of each side of square is 30 feet

Therefore, length of diagonal is given as:

$diagonal = \sqrt{2} \times 30\\\\diagonal = 1.414 \times 30 = 42.42$

Hence, the distance that the person walks 42.42 feet

3 0

4 years ago

A test has 20 true/false questions. What is the probability that a student passes the test if they guess the answers? Passing me

Minchanka [31]

Using the binomial distribution, it is found that:

The probability that the student will get 15 correct questions in this test by guessing is 0.0207 = 2.07%.

For each question, there are only two possible outcomes, either the guess is correct, or it is not. The guess on a question is independent of any other question, hence, the binomial distribution is used to solve this question.

Binomial probability distribution

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$