plz help i'm having a really hard time with this

Answer:

a = 9

Step-by-step explanation:

3a - 27 = 0

3a = 27

a = 27/3

a = 9

3*9  -  27 = 0

27 - 27 = 0

Answer:

a = 9

Step-by-step explanation:

3a-27=0

Add 27 to each side

3a = 27

Divide by 3

3a/3 = 27/3

a = 9

Answer:

a

   The  correct option is  B

b

   The  correct option is  D

Step-by-step explanation:

From the  question we are told that

     The level of significance is  [tex]\alpha = 0.05[/tex]

      The p-value is  [tex]p = 0.2761[/tex]

Considering question b

      Given that the  [tex]p< \alpha[/tex] then the null hypothesis is  rejected

Considering question b

Given that the original claim is The standard deviation of pulse rates of a certain group of adult males is more than 11 bpm

Then the null hypothesis is   [tex]H_o : \sigma = 11[/tex]

The  reason why the null hypothesis is write like this above is because a null hypothesis expression can not contain only a > or a < but only allows = [tex]\le , \ and \ \ge[/tex]

  and  the alternative hypothesis is  [tex]H_a : \sigma > 11[/tex]

Now given that the null hypothesis is rejected, it mean that there is sufficient evidence to support original claim

Answer:

x = 7

Step-by-step explanation:

L and M would be parallel if angle 2x -3 and the angle x + 4 are equal.

Thus, 2x - 3 = x + 4, so that x = 7

Answer:

235.6 units^3

Step-by-step explanation:

The formula for the volume of the oblique cone is the same as for the volume of a right circular cone:  V = (1/3)(base area)(height).

Here that comes to        V = (1/3)(π)(5 units)^2*(9 units), or

V = 75π units^3, or approximately 235.6 units^3

Answer:

235.5 cubic units

Step-by-step explanation:

Answer:

$106

Step-by-step explanation:

You have 100$ in savings account

Interest rate =3%

Time = 2 years

Total in 2 years:

The interest formula is as follows:

Amount Invested · Rate = Interest Earned

If we invest $100 at 3% interest per year,

how much do we earn that year?

Well based on our formula, we can simply multiply 100 · 3%.

Think of the 3% as 3/100.

So we have 100 · 3/100 and the 100's cancel and we're left with 3.

So $3 is earned in 1 year.

So after two years, you will have double that or $6.

Answer:

Cohen's d : 1.00

Step-by-step explanation:

We know that M₁ = 18, and M₂ = 14. Given that the pooled variance for the these two samples are 16, S²Pooled = 16, and therefore S - pooled = 4.

The formula to solve for the value of Cohen's d is as follows,

d = M₁ - M₂ / S - pooled,

d = 18 - 14 / 4 = 4 / 4 = 1

Therefore the value of Cohen's d = 1

Answer:

12). LM = 37.1 units

13). c = 4.6 mi

Step-by-step explanation:

12). LM² = 23² + 20² - 2(23)(20)cos(119)°

    LM² = 529 + 400 - 920cos(119)°

    LM² = 929 - 920cos(119)°

    LM = [tex]\sqrt{929+446.03}[/tex]

          = [tex]\sqrt{1375.03}[/tex]

          = 37.08

          ≈ 37.1 units

13). c² = 5.4² + 3.6² - 2(5.4)(3.6)cos(58)°

    c² = 29.16 + 12.96 - 38.88cos(58)°

    c² = 42.12 - 38.88cos(58)°

    c = [tex]\sqrt{42.12-20.603}[/tex]

    c = [tex]\sqrt{21.517}[/tex]

    c = 4.6386

    c ≈ 4.6 mi

Answer:

a) 952

b) 136

Step-by-step explanation:

Ratio of b:g = 3:4, based on this we have:

Number of spectacle wearers:

Number of those not wearing spectacles:

And this number equals to 612, then we can find the value of x:

a) Total number of pupils:

b) The difference in the number of boys and girls:

Answer:

total number of students: 952

number of girls more than boys :136 more girls

Step-by-step explanation:

1/3 of boys +3/8 girls= spectacles

612 people do not wear spectacles

3:4= boys: girls

total number of students

3+4=7

boys + girls = total ratio

7= total ratio

1/3×3=1 3/8×4=3/2

1+3/2=5/2

7-5/2=9/2 9/2=612 students

If 9/2=612 Then 7=?

7= 7÷ 9/2×612

=952 people

Girls more than boys

if 7= 952

3= 3/7 × 952=408 boys

if 7 = 952

4= 4/7 ×952=544girls

Girls - boys

544- 408 = 136 girls

Answer:

14x+4

Step-by-step explanation:

17x-3x=14x

Answer:

positively skewed to the right

Step-by-step explanation:

The measure of the central tendency is a profound way to describe the mean, median and mode. The measure of central tendency indicates where the center of distribution tends to be. The measure of central tendency provide a validity and answers whether the scores are high or generally low.

In this measure,The mean is usually pulled to the tail. The skewed is determined by where the tail goes, to the right side , it is positively skewed  and to the left side , it is known as negatively skewed distribution.

Given that:

In a frequency of distribution of 290 scores,

the mean  = 99

the median = 86

One would expect this distribution to be; positively skewed to the right  since the mean value is greater than the median value.

Complete  Question

In a random sample of  ten  people, the mean driving distance to work was  23.1 miles and the standard deviation was  6.6 miles. Assume the population is normally distributed and use the​ t-distribution to find the margin of error and construct a  99​%  confidence interval for the population mean Interpret the results.  Identify the margin of error.

Answer:

The  99% confidence interval is  [tex]16.32< \mu <29.88[/tex]

The interpretation is that there is 99% confidence that the true mean lies within the limits

The margin of error is  [tex]E = 6.783[/tex]

Step-by-step explanation:

From the question we are told that

   The sample mean is  [tex]\= x = 23.1[/tex]

     The standard deviation is  [tex]\sigma = 6.6 \ miles[/tex]

    The  sample size is  n = 10

Generally the degree of freedom is mathematically represented as

     [tex]df = n-1[/tex]

=>  [tex]df = 10-1[/tex]

=>  [tex]df =9[/tex]

Given that the confidence level is 99% , the n the level of significance is mathematically evaluated as

         [tex]\alpha = 100 - 99[/tex]

         [tex]\alpha =1\%[/tex]

        [tex]\alpha =0.01[/tex]

Next we obtain the critical value of  [tex]\frac{\alpha }{2}[/tex] with a df of  9  from from the student t-distribution table the value is  

          [tex]t _{\frac{\alpha }{2} , df } = 3.250[/tex]

Generally the margin of error is mathematically represented as

           [tex]E = t_{\frac{\alpha }{2} , df } * \frac{\sigma }{\sqrt{n} }[/tex]

          [tex]E = 3.250 * \frac{6.6 }{\sqrt{10} }[/tex]

         [tex]E = 6.783[/tex]

The 99% confidence interval is

      [tex]\= x - E < \mu < \= x + E[/tex]

=>   [tex]23.1 - 6.78 < \mu <23.1 + 6.78[/tex]

=>  [tex]16.32< \mu <29.88[/tex]

The interpretation is that there is 99% confidence that the true mean lies within the limits

Answer:

1.

d. (-14) + (-8)

2.

a. (-14) + 8

Step-by-step explanation:

(-14) - 8 is equal to (-14) + (-8) because we still add two negative values so the result wouldn't change.

(-14) - (-8) is equal to (-14) + 8 because there's two negative sign in front of 8 and two negative values multiplied makes a positive result.

Answer:

1. D  

2. A

Step-by-step explanation:

1.  It asks you what expression has the same value as (-14)-8.  All you need to do is find other equations that have the same value as that.  So the equation is -14-8.  IF a negative is outside a parenthesis with a positive number inside like -(+5), it is going to be -5.  If it's both negative: -(-5), it will be +5.  If it is both positive: +(+5), it is going to be +5.  

IMPORTANT!

- and + = -

- and - = +

+ and + = +

What we are looking for: -14-8

So choice A is (-14)+8 which is simplified to -14+8.  So, this one isn't right.

Choice B: 14-(-8)= 14+8.  So, it's incorrect.

Choice C: 14+(-8)= 14-8.  Again, it's not -14-8 so it's not right.

Choice D: (-14)+(-8)= -14-8.  This equation matches the one we are looking for!  So it's correct!

2. Same thing as number 1.  Let's simplify the equation it wants us to find first.  

(-14)-(-8)= -14+8

So -14+8 is what we are looking for.

Choice A: (-14)+8= -14+8.  It matches!  So it is correct.  Let's look at the other options anyway.

Choice B: 14-(-8)= 14+8.  Nope.  Not right.

Choice C: 14+(-8)= 14-8 because - always beats +.  So, this one is also incorrect.

Choice D: (-14)+(-8)= -14-8.  Oops, this is also wrong.  So choice A is the right answer.

Keep in mind, when you start getting questions like this with numbers inside the parenthesis as well, you want to remember the same rules for positive and negative, but also multiply the numbers together:

(When there is a number outside and inside a parentheses, multiply them.)

2(5)=10, CORRECT!    2+(5) is not 2 times 5.  It's whatever is closest to the parentheses, in this case being the positive sign.  So + and 5 is just 5!

IMPORTANT!

-2(-5)= - and - is positive, so positive (2 times 5).  Positive 10.

-2(+5)= - and + is negative, so negative (2 times 5). Negative 10.

+2(+5)= + and + is positive, so positive (2 times 5).  Positive 10.

====================================================

Explanation:

Both AB and XY are the first two letters of ABC and XYZ respectively. So we have one fraction of AB/XY = 2/7.

AC and XZ are the first and last letters of ABC and XYZ respectively. We can form another fraction AC/XZ. I'm dividing in the same order of small over large to keep things consistent. As you can probably guess, the order of the letters ABC and XYZ are important so we see how the angles match up and how the proportional sides match up.

Because the triangles are similar, the two fractions formed earlier are equal to one another.

The equation we need to solve is AB/XY = AC/XZ

-----

AB/XY = AC/XZ

2/7 = 3/N ... plug in given values

2N = 7*3 .... cross multiply

2N = 21

N = 21/2 .... divide both sides by 2

N = 10.5

ZX is 10.5 units long.

Answer:

( y-5) ^2 =-12(x-2)

Step-by-step explanation:

focus at (2,2) and a directrix of x=8

Using the equation

( y-k) ^2 = 4p(x-k)

where ( h,k) is the vertex

The vertex is 1/2 way between the focus and the directrix

( 2+8)/2 , 2

5,2 is the vertex

( y-5) ^2 = 4p(x-2)

distance from the focus to the vertex and from the vertex to the directrix is  

| p|

2-5 = p

-3 = p

( y-5) ^2 = 4*-3(x-2)

( y-5) ^2 =-12(x-2)

Answer:

(x + 3i) * (x - 3i) = x^2 + 3xi - 3xi - 9(i^2) = x^2 + 9

Step-by-step explanation:

Answer: hey

Step-by-step explanation:

Answer:

[tex]\large \boxed{{y=18}}[/tex]

Step-by-step explanation:

[tex]1(y+3)=2(y+-4)+- 7[/tex]

Expand brackets.

[tex]y+3=2y-8+- 7[/tex]

Simplify.

[tex]y+3=2y-15[/tex]

Add -y and 15 on both sides.

[tex]y+3-y+15=2y-15-y+15[/tex]

Simplify.

[tex]3+15=2y-y[/tex]

[tex]18=y[/tex]

Answer:

18

Step-by-step explanation:

● 1 (y+3) = 2 (y+(-4) )+ (-7)

When you multiply by 1 you get the same result.

● y+3 = 2 (y+(-4))+(-7)

When you have a + sign with a - sign write -.

● y+3 = 2(y-4)-7

Multiply 2 by (y-4) and simplify

● y+3 = (2y-8)-7

● y+3 = 2y -8-7

● y+3 = 2y -15

Add 15 to both sides

● y +3+15 = 2y-15 +15

● y + 18 = 2y

Sibstract y from both sides

● y +18 - y = 2y -y

● 18 = y

Answer:

[tex]\large \boxed{x\° = 130}[/tex]

Step-by-step explanation:

The triangle is an isosceles triangle. The base angles are equal.

Angles in a triangle add to 180 degrees.

[tex]y+65+65=180\\y+130=180\\y=50[/tex]

Angles on a straight line add up to 180 degrees.

[tex]x+50=180\\x=130[/tex]

Answer:

[tex]\huge\boxed{\sf x = 130\ degrees}[/tex]

Step-by-step explanation:

The measure of exterior angle is equal to the sum of non-adjacent interior angles.

So,

x = 65 + 65

x = 130 degrees

Answer:

Use the student t distribution

Step-by-step explanation:

Here is the formula

t = (x - u) ÷(s/√N)

From the information we have in the question:

n = 150

s = 550

x = 3400

u = mean = 2400

= 3400 - 2400÷ 500/√150

= 1000/44.9

= 22.27

At 0.05 significance level, df = 149 so t tabulated will be 1.65.

Answer:

it is 9%

Step-by-step explanation: the socks persent is the correct answer

Answer: D. 61%

Step-by-step explanation:

Answer:

Step-by-step explanation:

[tex]12-8x=5\\\\Collect\:like\:terms\\\\-8x =5-12\\\\-8x = -7\\\\Divide\:both\:sides\:by -8\\\frac{-8x}{-8} \\=\frac{-7}{-8} \\\\x = 0.875\\\\x = 0.88[/tex]

Answer:

see explanation

Step-by-step explanation:

If f(x) and [tex]f^{-1}[/tex] are inverse functions, then

f([tex]f^{-1}[/tex])(x) = x

Thus substitute x = [tex]f^{-1}[/tex] (x) into f(x)

f([tex]\frac{x+6}{5}[/tex] )

= 5 ([tex]\frac{x+6}{5}[/tex] ) - 6

= x + 6 - 6

= x

Thus f(x) and [tex]f^{-1}[/tex] (x) are inverse functions

Answer:

For the functions to coincide, the value of k in y = (kx)3 must be smaller than in y = kx3. This is because the value of y changes more rapidly when k is cubed inside the parentheses. The behavior of the functions is similar since a vertical stretch is similar to a horizontal compression.

Step-by-step explanation:

PLATO

From your earlier questions, we found

[tex]2\sin(4\pi t)+5\cos(4\pi t)=\sqrt{29}\sin\left(4\pi t+\tan^{-1}\left(\dfrac52\right)\right)[/tex]

so the wave has amplitude √29. The weight's maximum negative position from equilibrium is then -√29, so you are solving for t in the given interval for which

[tex]\sqrt{29}\sin\left(4\pi t+\tan^{-1}\left(\dfrac52\right)\right)=-\dfrac{\sqrt{29}}2[/tex]

Divide both sides by √29:

[tex]\sin\left(4\pi t+\tan^{-1}\left(\dfrac52\right)\right)=-\dfrac12[/tex]

Take the inverse sine of both sides, noting that we get two possible solution sets because we have

[tex]\sin\left(\dfrac{7\pi}6\right)=\sin\left(\dfrac{11\pi}6\right)=-\dfrac12[/tex]

and the sine wave has period 2π, so [tex]\sin x=\sin(x+2\pi)=\sin(x+4\pi)=\cdots[/tex].

[tex]\implies 4\pi t+\tan^{-1}\left(\dfrac52\right)=\dfrac{7\pi}6+2n\pi[/tex]

OR

[tex]\implies 4\pi t+\tan^{-1}\left(\dfrac52\right)=\dfrac{11\pi}6+2n\pi[/tex]

where n is any integer.

Now solve for t :

[tex]t=\dfrac{\frac{7\pi}6+2n\pi-\tan^{-1}\left(\frac52\right)}{4\pi}[/tex]

OR

[tex]t=\dfrac{\frac{11\pi}6+2n\pi-\tan^{-1}\left(\frac52\right)}{4\pi}[/tex]

We get solutions between 0 and 0.5 when n = 0 of t ≈ 0.196946 and t ≈ 0.363613.

Complete Question

On the uploaded image is a similar question that will explain the given question

Answer:

The value of k is  [tex]k = 214285.7[/tex]

The percentage  of the oil that will be cleaned is [tex]x = 80.77\%[/tex]

Step-by-step explanation:

From the question we are told that

   The  cost of cleaning up the spillage is  [tex]C = \frac{ k x }{100 - x }[/tex]  [tex]x \le x \le 100[/tex]

     The  cost of cleaning x =  70% of the oil is  [tex]C = \$500,000[/tex]

Now at  [tex]C = \$500,000[/tex] we have  

       [tex]\$ 500000 = \frac{ k * 70 }{100 - 70 }[/tex]

       [tex]\$ 500000 = \frac{ k * 70 }{30 }[/tex]

      [tex]\$ 500000 = \frac{ k * 70 }{30 }[/tex]

      [tex]k = 214285.7[/tex]

Now  When  [tex]C = \$900,000[/tex]

       [tex]x = 80.77\%[/tex]

Answer:

8 3/4

Step-by-step explanation:

The decimal 3.5 as an improper fraction is 35/10.

Answer:

[tex]8\frac{3}{4}[/tex]

Step-by-step explanation:

To write as a mixed number means that you will have a whole number and a fraction together. To find the mixed fraction version, see how many times the denominator (bottom) fits into the numerator (top) evenly.

4, 8, 12, 16, 20, 24, 28, 32, 36

1   2  3   4    5    6    7    8     9

4 can go into 35 '8' times without being greater than the numerator. 8 is the whole number. Now subtract the original numerator by the product of 4 and 8, which is 32:

[tex]35-32=3[/tex]

3 is the new numerator. Keep the same denominator. Insert all values:

[tex]\frac{35}{4}=8\frac{3}{4}[/tex]

:Done

Answer: A = 2,034.356 ≈ $2,034.36

$2,034.36 will be in the account in 3 years

Step-by-step explanation:

Given that ;

P = $1,700

Rate r = 6%

Time period (t) = 3 years

now to find how much money will be in the account in 3 years

we say;

A = P ( 1 + r/n )^nt

A = 1,700 ( 1 + 0.06/12) ¹²ˣ³

A = 1,700 ( 1.19668)

A = 2,034.356 ≈ $2,034.36  

Answer:

Step-by-step explanation:

The sequence of the problem above is an arithmetic sequence

For an nth term in an arithmetic sequence

F(n) = a + ( n - 1)d

where a is the first term

n is the number of terms

d is the common difference

To find the equation first find the common difference

0.65 - 0.5 = 0.15 or 0.80 - 0.65 = 0.15

The first term is 0.5

Substitute the values into the above formula

That's

f(n) = 0.5 + (n - 1)0.15

f(n) = 0.5 + 0.15n - 0.15

The final answer is

Hope this helps you

Answer:

Step-by-step explanation:

Took the math test on edge

Answer:

  145 degrees

Step-by-step explanation:

Adjacent angles in a parallelogram are supplementary.

  d2 = 180° -d1 = 180° -35°

  d2 = 145°