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Answer:

The required length of AB is 7.28 units.

Answer:

Step-by-step explanation:

189² = 215² + 123² - 2(215)(123)cos x°

35,721 = 46,225 + 15,129 - 52,890 cos x°

35,721 = 61,354 - 52,890 cos x°

52,890 (cos x° ) = 25,633

cos x° = 25,633 ÷ 52,890 ≈ 0.4846

x° ≈ 61.01°

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Answer:

  10

Step-by-step explanation:

The sum of terms of an arithmetic series is ...

  Sn = (2a +d(n -1))·n/2 = (2an +dn^2 -dn)/2

For the series with first term 2 and common difference 3, the sum is 155 for n terms, where ...

  155 = (3n^2 +n(2·2 -3))/2

Multiplying by 2, we have ...

  3n^2 +n -310 = 0 . . . . . arranged in standard form

Using the quadratic formula, the positive solution is ...

  n = (-1 +√(1 -4(3)(-310)))/(2(3)) = (-1 +√3721)/6 = (61 -1)/6 = 10

10 terms of the series will have a sum of 155.

Step-by-step explanation:

[tex]\displaystyle \ \Large \boldsymbol{} S_n=\frac{2a_1+d(n-1)}{2} \cdot n =155 \\\\ \frac{4+3(n-1)}{2} \cdot n =155 \\\\\\ 4n+3n^2-3n=310 \\\\ 3n^2+n-310=0 \\\\D=1+3720=3721=61^2\\\\n_1=\frac{61-1}{6} =\boxed{10} \\\\\\n_2=\frac{-61-1}{3} \ \ \o[/tex]

[tex] \begin{cases} \\ \large\bf{\green{ \implies}} \tt \: - \: \frac{1}{2} \: m \: = \: - 9 \\ \\ \large\bf{\green{ \implies}} \tt \: - \frac{1 \: m}{2} \: = \: - 9 \\ \\ \large\bf{\green{ \implies}} \tt \: - 1m \: = \: - 9 \: \times \: 2 \\ \\ \large\bf{\green{ \implies}} \tt \: - 1m \: = \: - 18 \\ \\ \large\bf{\green{ \implies}} \tt \: m \: = \: \frac{ \cancel- 18}{ \cancel - 1} \\ \\ \large\bf{\green{ \implies}} \tt \: m \: = \: \frac{18}{1} \\ \\ \large\bf{\green{ \implies}} \tt \: m \: = \: 18 \: \\ \end{cases}[/tex]

Answer:

The right answer is the 2nd one

hope it will help :)

The given sum is option B. 2xy√y + 2xy²√x.

Expressions are mathematical statements which consist of two or more terms and terms are connected to each other using mathematical operators like addition, multiplication, subtraction and so on.

Given expression of sum is,

√(x²y³) + 2√(x³y⁴) + xy √y

We have to find the sum.

√(x²y³) = √x² √y³ = x√y³ = x√(y²)√y = xy√y

Now,

2√(x³y⁴) = 2[√x² √x √(y²)²] = 2x√x y² = 2xy²√x

Substituting these,

√(x²y³) + 2√(x³y⁴) + xy √y = xy√y + 2xy²√x + xy √y

                                          = 2xy√y + 2xy²√x

Hence the equivalent sum is 2xy√y + 2xy²√x.

Learn more about Expressions sum here :

https://brainly.com/question/15284271

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x = 4

Every step shown. Once you become used to doing this you will almost be able to do the basic one's in your head without writing much down.

Explanation:

Let the unknown value be  

x

Converting the words into numbers:

First part: "15 times a certain number"  → 15 x

Second part: "plus 5 times the same number" → 15 x + 5 x

The last part: " is 80" ->  15x + 5 x = 80

We are counting  x ' s . 15 of them plus another 5 of them gives a total of 20.

So 15 x + 5 x = 20 x = 80

Divide both sides by 20

20 x ÷ 20 = 80÷ 20

20/20x=80/20

x=4

Let the number be x

ATQ

[tex]\\ \sf\longmapsto 15x+5x=80[/tex]

[tex]\\ \sf\longmapsto (15+5)x=80[/tex]

[tex]\\ \sf\longmapsto 20x=80[/tex]

[tex]\\ \sf\longmapsto x=\dfrac{80}{20}[/tex]

[tex]\\ \sf\longmapsto x=4[/tex]

Option 3 is not possible

-60.2 + 32 = -60.2 + 60

And these are not equal

Rest all options have x and are solvable

Must click thanks and mark brainliest

Answer:

(a) You will get ten

Step-by-step explanation:

single cell = 3 min

30 min = ?

30 divided by 10 = 3

Have a good day!

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Answer:

   10·2^-8 grams

Step-by-step explanation:

The each day, the initial amount for that day is multiplied by 1/2. After 8 days, the initial amount has been multiplied by (1/2)^8, where the exponent of 8 signifies that (1/2) is a factor 8 times in the product.

After n days, the quantity remaining is ...

  q(n) = 10·(1/2)^n = 10·2^(-n)

after 8 days the remaining amount is ...

  q(8) = 10·2^-8 . . . grams

Answer:

option A

Step-by-step explanation:

wx and zy making 90 angle with each other therefore they are perpendicular.

wx and ab making 0 angle with each other therefore they are parallel

Answer:

x=-17/5

Step-by-step explanation:

–5(–2x – 5) – 2 – 1= -12

+10x+25-2-1=-12

10x+22=-12

10x=-12-22

10x=-34

x=-34/10

x=-17/5

Step-by-step explanation:

Open the brackets

10x +25 -2 - 1= -12

Collect the like terms

10x = -12-25+2+1

10x = -34

Divide both sides by 10

Therefore,x = -34/10 = -3.4

Answer:

D. 11

Step-by-step explanation:

First apply the secant-secant theorem to find the value of x.

Thus,

VU(TU + VU) = VW(BW + VW) (secant-secant theorem)

Substitute

(7)(x + 4 + 7) = (9)(-2 + x + 9)

7(x + 11) = 9(7 + x)

7x + 77 = 63 + 9x

Collect like terms

7x - 9x = 63 - 77

-2x = -14

Divide both sides by -2

x = 7

✔️Find TU

TU = x + 4

Substitute get value of x

TU = 7 + 4 = 11

Answer:

11

Step-by-step explanation:

Answer:

6/15.

14/42.

Step-by-step explanation:

2/5 = 6/x

Cross multiply:

2x = 5*6

x = 15

Similarly:

10/30 = 14/x

10x = 30*14

x = 420/10

x = 42.

Answer:

ratio of water and milk=2:3

i.e. water=2

milk=3

now adding 1 liter of water in 2

2+1=3

and 1 liter of milk in 3

3+1=4

hence,

the new ratio is 3:4

Step-by-step explanation:

i hope this will help

plz mark as brainliest

Answer:

f(7)=109

Step-by-step explanation:

Since f(a)=7 then you just imput 7 on each x like this f(7)=8+13(7)+10= 109

Answer:

$11.25

Step-by-step explanation:

Total money given to the taxi driver=36+25% of 36=45

Each person will pay (45/4)=11.25

Answer:

1 kilometer in 1 hour

Step-by-step explanation:

unit rate is km(kilometer) per hour(hr)

1/3 km = 1/3 hr

multiply both sides by 3

1 km in 1 hour

Step-by-step explanation:

hi

what is your question?

Step-by-step explanation:

please tell full questions

Answer:

Because it is not an equation.

Step-by-step explanation:

[tex] log(x) \times log(2) \\ = log(x + 2) [/tex]

No piece of information is supplied to choose from ; However, the requirements for the test statistic of the hypothesis in question is given below.

Answer:

Kindly check explanation

Step-by-step explanation:

The hypothesis in the question above which is to be tested is a one sample proportion test ;

The test statistic formula for a one sample proportion test is given as :

Test statistic = (Phat - P) / √[P(1 - P) / n] ;

Where;

Phat = sample proportion

P = population proportion

n = sample size

Sample proportion = x / n ;

Therefore, once the parameters (Sample proportion, population proportion and sample size are given) then obtaining the test statistic is possible.

When a person does not have enough time he must should take the faster and effective route in this case carlos does not have time for individual interviews or phone calls. Focus group will not work i guess because discussion takes time so i guess it should be survey. I am not sure but it should be Survey or Focus Group

Must click thanks and mark brainliest

Option C

Customers will think she is very busy

A messy desk indicates that the person is very busy.

Must click thanks and mark brainliest

Answer:

C(t) = 20t

Step-by-step explanation:

The graph of C(t) appears to be linear

The y intercept is 0

The slope is 200/10 = 20

y = mx+b  where m is the slope and b is the y intercept

y = 20x+0

y = 20x

C(t) = 20t

Answer:

the answer is c (t) = 20 t

Step-by-step explanation:

[tex]\sf{}[/tex]

:,-)

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Answer:

–81

Step-by-step explanation:

Answer:

I don't knowledge bro sorry

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Answer:

  A.  96

Step-by-step explanation:

The surface area is the sum of the areas of the two triangular bases and the areas of the three rectangular lateral faces.

  A = 2(1/2)bh + PH

where b is the base of the triangle, h is its height, P is the perimeter of the triangle, and H is the height of the prism.

  A = (3 cm)(4 cm) +(3 +4 +5 cm)(7 cm) = 12 cm² +84 cm²

  A = 96 cm²

The surface area of the triangular prism is 96 square cm.

Step-by-step explanation:

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Answer:

  (f•g)(x) = -16x^3 +10x^2 -14x

Step-by-step explanation:

  (f•g)(x) = f(x)•g(x) = (-2x)(8x^2 -5x +7)

Use the distributive property:

  (f•g)(x) = -16x^3 +10x^2 -14x

(a) You can parameterize C by the vector function

r(t) = (x(t), y(t) ) = P (1 - t ) + Q t = (2 - 2t, 7t )

where 0 ≤ t ≤ 1.

(b) From the above parameterization, we have

r'(t) = (-2, 7)   ==>   ||r'(t)|| = √((-2)² + 7²) = √53

Then

ds = √53 dt

and the line integral is

[tex]\displaystyle\int_C(9x(t)+5y(t))\,\mathrm ds = \boxed{\sqrt{53}\int_0^1(17t+18)\,\mathrm dt}[/tex]

(c) The remaining integral is pretty simple,

[tex]\displaystyle\sqrt{53}\int_0^1(17t+18)\,\mathrm dt = \sqrt{53}\left(\frac{17}2t^2+18t\right)\bigg|_{t=0}^{t=1} = \boxed{\frac{53^{3/2}}2}[/tex]

First, write out the equation in slope intercept form.

-3y= -2x+6

y= 2/3x -2

The slope of the equation is 2/3, m.

Substitute the slope and coordinate into y=mx+b. Since it’s parallel, the slope remains the same.

6= 2/3(2)+b

6= 4/3+b

14/3=b

y= 2/3x + 14/3