All categories

3 years ago

Which expression is equivalent to 9 x squared minus 2 y + 3 x squared minus 3 y?

Mathematics

2 answers:

lyudmila [28]3 years ago

8 0

Answer:

The correct answer is 11 x squared + 2 y + x squared minus 3 y

Step-by-step explanation:

Just took the test on Edg. Hope it helps :)

anzhelika [568]3 years ago

7 0

Answer:

The correct answer is 11 x squared + 2 y + x squared minus 3 y

Step-by-step explanation:

Have put thought into

You might be interested in

In a clinical study, volunteers are tested for a gene that has been found to increase the risk for a disease. The probability th

MrRa [10]

Answer:

a) 0.984

b) 20 people

Step-by-step explanation:

If The probability that a person carries the gene is 0.1, then in a sample of 20 people, 2 should carry the gene.

Now, we want to know how many samples there are with this property.

Since we have 20 elements where 18 are alike (do not carry the gene) and 2 are alike (carry the gene), we have to compute the number of permutations of 20 elements in which 18 are alike and 2 are alike. This number is

$\frac{20!}{18!2!}=190$

In this 190 20-tuples there are only 3 where the 2 carriers of the gene are in the first 3 places, namely

(1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0)

(1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0)

(0,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0)

where 1=carries the gene, 0=does not carry the gene.

So there are 190-3 = 187 elements in which the first 3 elements have no 2 carriers, hence the probability that 4 or more people will have to be tested until 2 of them with the gene are detected is 187/190 = 0.984 (98.4%) rounded to three decimal places.

Given that the probability that a person carries the gene is 0.1, then in a sample of 20 people, 20*0.1 = 2 should carry the gene.

4 0

3 years ago

How can you tell if the solution is one value,all real numbers,or no solutions

zysi [14]

One value: would be a single valued function, or just one answer.

Real numbers would be: natural numbers, whole numbers, integers, rational numbers (fractions and repeating or terminating decimals), and irrational numbers.

No solution: there is no answer to the question.

8 0

3 years ago

find the volume of the solid formed by revolving the region bounded by the graphs of y = 4x - x^2 and f(x) = x^2 from [0,2] abou

Neko [114]

Answer:

$v = \frac{32\pi}{3}$

$v=33.52$

Step-by-step explanation:

Given

$f(x) = 4x - x^2$

$g(x) = x^2$

$[a,b] = [0,2]$

Required

The volume of the solid formed

Rotating about the x-axis.

Using the washer method to calculate the volume, we have:

$\int dv = \int\limit^b_a \pi(f(x)^2 - g(x)^2) dx$

Integrate

$v = \int\limit^b_a \pi(f(x)^2 - g(x)^2)\ dx$

$v = \pi \int\limit^b_a (f(x)^2 - g(x)^2)\ dx$

Substitute values for a, b, f(x) and g(x)

$v = \pi \int\limit^2_0 ((4x - x^2)^2 - (x^2)^2)\ dx$

Evaluate the exponents

$v = \pi \int\limit^2_0 (16x^2 - 4x^3 - 4x^3 + x^4 - x^4)\ dx$

Simplify like terms

$v = \pi \int\limit^2_0 (16x^2 - 8x^3 )\ dx$

Factor out 8

$v = 8\pi \int\limit^2_0 (2x^2 - x^3 )\ dx$

Integrate

$v = 8\pi [ \frac{2x^{2+1}}{2+1} - \frac{x^{3+1}}{3+1} ]|\limit^2_0$

$v = 8\pi [ \frac{2x^{3}}{3} - \frac{x^{4}}{4} ]|\limit^2_0$

Substitute 2 and 0 for x, respectively

$v = 8\pi ([ \frac{2*2^{3}}{3} - \frac{2^{4}}{4} ] - [ \frac{2*0^{3}}{3} - \frac{0^{4}}{4} ])$

$v = 8\pi ([ \frac{2*2^{3}}{3} - \frac{2^{4}}{4} ] - [ 0 - 0])$

$v = 8\pi [ \frac{2*2^{3}}{3} - \frac{2^{4}}{4} ]$

$v = 8\pi [ \frac{16}{3} - \frac{16}{4} ]$

Take LCM

$v = 8\pi [ \frac{16*4- 16 * 3}{12}]$

$v = 8\pi [ \frac{64- 48}{12}]$

$v = 8\pi * \frac{16}{12}$

Simplify

$v = 8\pi * \frac{4}{3}$

$v = \frac{32\pi}{3}$

$v=\frac{32}{3} * \frac{22}{7}$

$v=\frac{32*22}{3*7}$

$v=\frac{704}{21}$

$v=33.52$

8 0

3 years ago

A population of 30 deer is introduced into a wildlife sanctuary. It is estimated that the sanctuary can sustain up to 200 deer,

gogolik [260]

Answer:

After one year the population will be 33 deers, and after two years it will be 36 deers.

Step-by-step explanation:

Given that a population of 30 deer is introduced into a wildlife sanctuary, and it is estimated that the sanctuary can sustain up to 200 deer, and absent constraints, the population would grow by 10% per year, to predict the population after one year and after two years, the following calculations must be performed:

30 x 1.1 = X

33 = X

30 x 1.1 ^ 2 = X

30 x 1.21 = X

36.3 = X

Therefore, after one year the population will be 33 deers, and after two years it will be 36 deers.

7 0

3 years ago

7 - 3b-2(0 + 3 - 2b)

Naddika [18.5K]

Step-by-step explanation:

7 - 3b-2(0 + 3 - 2b)

To simplify the expression in the box, Fatua used

these steps:

Step 1:7 - 3b-2(3 - 3b)

Step 2:7 - 3-6-36-

Step 3: -13 - 66

Did Fatua calculate correctly? if nnot, in what step

did she make her FIRST mistake?

6 0

2 years ago

Read 2 more answers