What degree of rotation about the origin will cause the triangle below to map
onto itself?
A.90
B.270
C.360
D.180

Answer:

D.

Step-by-step explanation:

.

Observe that

5/12 = 1/4 + 1/6

so that

tan(5π/12) = tan(π/4 + π/6)

Then

tan(5π/12) = sin(π/4 + π/6) / cos(π/4 + π/6)

… = (sin(π/4) cos(π/6) + cos(π/4) sin(π/6)) / (cos(π/4) cos(π/6) - sin(π/4) sin(π/6))

… = (cos(π/6) + sin(π/6)) / (cos(π/6) - sin(π/6))

(since sin(π/4) = cos(π/4) = 1/√2)

… = (√3/2 + 1/2) / (√3/2 - 1/2)

… = (√3 + 1) / (√3 - 1)

… = (√3 + 1) / (√3 - 1) × (√3 + 1) / (√3 + 1)

… = (√3 + 1)² / ((√3)² - 1²)

… = ((√3)² + 2√3 + 1²) / (3 - 1)

… = (3 + 2√3 + 1) / 2

… = (4 + 2√3) / 2

… = 2 + √3 … … … (C)

If you insist on using the half-angle identity, recall that

sin²(x) = (1 - cos(2x))/2

cos²(x) = (1 + cos(2x))/2

==>   tan²(x) = (1 - cos(2x)) / (1 + cos(2x))

Let x = 5π/12. The angle x lies in the first quadrant, so we know tan(x) is positive.

==>   tan(x) = +√[(1 - cos(2x)) / (1 + cos(2x))]

We also know

cos(2x) = cos(5π/6) = -√3/2

which means

tan(x) = tan(5π/12) = √[(1 - (-√3/2)) / (1 + (-√3/2))]

… = √[(1 + √3/2) / (1 - √3/2)]

… = √[(2 + √3) / (2 - √3)]

… = √[(2 + √3) / (2 - √3) × (2 + √3) / (2 + √3)]

… = √[(2 + √3)² / (2² - (√3)²)]

… = √[(2 + √3)² / (4 - 3)]

… = √[(2 + √3)²]

… = 2 + √3

Answer:

The expected value is an expression of the weighted average and can be taken as the (arithmetic) mean

As the number of trials is increased in a binomial experiment, the expected values obtained, in each of the set of trials continuously tend to the theoretical expected value

Step-by-step explanation:

Hello,

Answer D

[tex]\begin{array}{|c|c|}x&y\\--&-------------\\-1&-3*\sqrt{-1+1} =-3*0=0\\0&-3*\sqrt{0+1} =-3*1=-3\\3&-3*\sqrt{3+1} =-3*2=-6\\8&-3*\sqrt{8+1} =-3*3=-9\\15&-3*\sqrt{15+1} =-3*4=-12\\--&-------------\\\end{array}[/tex]

Answer:

4th option

Step-by-step explanation:

From

- x - 2y = - 4 ( add x to both sides )

- 2y = x - 4 ( add 4 to both sides )

- 2y + 4 = x , so

Substitute x = - 2y + 4 into the second equation

Answer:

c = 4

See explanation

Step-by-step explanation:

Given:

4c = 3c - 4

Your calculation:

4c = 3c + 4

4c = 4 - 3c

4c = 1c

c = 4/1

c= 4

Correct calculation:

4c = 3c + 4

Collect like terms by subtracting 3c from both sides

4c - 3c = 3c + 4 - 3c

c = 4

Check:

4c = 3c + 4

4(4) = 3(4) + 4

16 = 12 + 4

16 = 16

Therefore,

Your final answer is correct but your method of calculation is not correct

Answer:

The correction option is B.

Step-by-step explanation:

Answer:

B. One

Step-by-step explanation:

If it is a single payment loan, the title is self explanatory <3

Answer:

Reflection symmetry

Step-by-step explanation:

For an image to have reflection symmetry, it must appear the same after reflected over any line. In this case, there is a vertical line of symmetry we can reflect the image and not appear to have made any changes.

For an image to rotational symmetry, it needs to appear the same after being rotated some degree in either direction less than one full turn. In this case, there exists no rotation less than one full turn where we can rotate the image so it appears the exact same as it was before.

Therefore, this image only has reflection symmetry.

Answer:

Vaccines are made of mixtures that contain either parts of pathogens or whole pathogens that prepare the body's defenses to fight against the pathogens.

hope it helps.

Answer:Vaccines are made of mixtures that contain either parts of pathogens or whole pathogens that prepare the body's defenses to fight against the pathogens.

Step-by-step explanation:

v₁·v₂ is -18 which is correct option(D)

Arithmetic operations can also be specified by the subtract, divide, and multiply built-in functions.

The operator that perform arithmetic operation are called arithmetic operators .

Operators which let do basic mathematical calculations

+ Addition operation : Adds values on either side of the operator.

For example 4 + 2 = 6

- Subtraction operation : Subtracts right hand operand from left hand operand.

for example 4 -2 = 2

* Multiplication operation : Multiplies values on either side of the operator

For example 4*2 = 8

/ Division operation : Divides left hand operand by right hand operand

For example 4/2 = 2

Given that,

v1 = (3,-4) and v2 = (2,6)

To determine v₁·v₂

v₁·v₂ = 3·(2) - 4·(6)

v₁·v₂ = 6 - 24

v₁·v₂ = -18

Hence, the v₁·v₂ is -18.

Learn more about Arithmetic operations here:

brainly.com/question/25834626

#SPJ2

Answer:I don’t speak Spanish so I can’t help

Step-by-step explanation:

Answer:

could you show the ine?

Step-by-step explanation:

Answer: Choice D

The graph will be discrete because there is no such thing as a partial person to sign up, and the booth is set up once each day for sign ups.

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

Explanation:

Let's start with the independent variable d. This acts as the variable x. It's the input. The value of d only takes on positive whole numbers (eg: d = 1, d = 2, d = 3, etc). We cannot have something like d = 2.718

So this bit of evidence shows that our function is discrete. Discrete input values (d) plug into the function to produce corresponding discrete output values (m).

Furthermore, we know that m is discrete because the number of people cannot be a fractional or decimal number. We can't have half a person for instance.

---------------

A quick way to see if a set is discrete or continuous is to ask the question: "is it possible to apply the midpoint formula for ANY two values, and have the output make sense?"

So a set like {1,2,3,4,5,...} is discrete because the midpoint of 2 and 3 is 2.5, but that value is not in the set mentioned.

In other words, discrete sets have "gaps" so to speak, while continuous ones do not.

---------------

Another useful property is that let's say that a < x < b, and x is drawn from the domain set. This reduced set will be finite if we're dealing with discrete data. Eg: The set {1,2,3,4,5,...} has the subset {2,3,4} which is finite and discrete.

In contrast, the subset of real numbers x such that [tex]2 \le x \le 4[/tex] is continuous and this subset is infinitely large (has infinitely many members) because we could have things like 2.718 or 3.14 etc

Let the height of the rectangle = h

2b + 2h = 100

2(38) + 2h = 100

2h = 100 - 76

h = 12mm

area of rectangle = base x height

= 38 x 12

= 456mm²

Answer:

456mm²

Step-by-step explanation:

using formula;

b/2( P - 2b) = A

substitute values

Answer:

The answer is (A) 75

Step-by-step explanation:

Answer:

A 75

Step-by-step explanation:

10*5(number of ducks that lay an egg everyday)

5*5(number of ducks that lay an egg every second day)

10*5 + 5*5

[tex]\displaystyle\ (\sqrt{25x-16} )^2=\ (i)^2 \\\\ 25x-16=-1 \\\\25x=15\\\\\boxed{x=\frac{3}{5}}[/tex]

Answer:

Hope that will help you

Step-by-step explanation:

BD = 14.5

Answer:

THE ANSWER IS UNLIMITED

Step-by-step explanation:

THE REASON IT'S UNLIMITED IS BECAUSE YOU CAN HAVE ALL TYPES OF SHIRTS, FROM JERSEYS TO DRESS SHIRTS, TO T-SHIRTS.

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

Explanation:

Choice B has the GCF x we can factor out like so

10x^4-5x^3+70x^2+3x = x(10x^3-5x^2+70x+3)

Showing that choice B is not prime. If a polynomial can be factored, then we consider it not prime. It's analogous to saying a number like 15 isn't prime because 15 = 3*5, ie 15 can be factored into something that doesn't involve 1 as a factor.

In contrast, we consider 7 prime because even though 7 = 1*7, there aren't any other ways to write this integer as a factorization if we don't involve 1.

-----------------------------------

Choice C is a similar story. This time we can factor out 3

3x^2 + 18y = 3(x^2 + 6y)

So we can rule this out as well.

-----------------------------------

Choice D is a bit tricky, but we can use the difference of cubes factoring rule

a^3 - b^3 = (a-b)(a^2+ab+b^2)

where in this case a = x and b = 3y^2

Note how b^3 = (3y^2)^3 = 3^3*(y^2)^3 = 27y^(2*3) = 27y^6

All of this means choice D can be factored and it's not prime either.

------------------------------------

We've ruled out choices B through D. The answer must be choice A.

If you let w = x^2, then w^2 = x^4

The polynomial w^2+20w-100 is prime because setting it equal to zero and solving for w leads to irrational solutions. I'm assuming your teacher wants you to factor over the rational numbers.

Because w^2+20w-100 can't be factored over the rational numbers, neither can x^4+20x^2-100. This confirms that choice A is prime.

Answer:

a

Step-by-step explanation:

The perpendicular distance from the y- axis is the value of the x- coordinate, so

perpendicular distance is 3 units

Answer: determining if the training was responsible for any changes in performance

Step-by-step explanation:

Training evaluation is the process of analyzing if training are efficient and effective.

A problem with the pre-/post-measure of training evaluation is determining if the training was responsible for any changes in performance.

Answer:

1/8 of an hour

Step-by-step explanation:

3/4 x 1/6 = 3/24 = 1/8

Hope this helps!

Answer:

where is the question oooo

Answer: 21, 28

Step-by-step explanation:

Use the Pythagorean Theorem [tex]a^{2}+b^{2}=c^{2}[/tex]:

Substitute in the values & solve:

[tex]x^{2}+(x+7)^{2}=35^{2}\\x^{2}+x^{2}+14x+49=1225\\2x^{2}+14x+49-1225=0\\2x^{2}+14x-1176=0\\2(x^{2}+7x-588)=0\\2(x + 28)(x - 21)=0\\x_{1}=-28, x_{2}=21[/tex]

-28 is not a possible solution since you can't have negative inches...

Hello,

[tex]Data:\\\\\begin{array}{|c|c|c|c|c|}Year&French&Spanish&German&Total\\----&----&----&----&---\\Y10&-&-&-&54\\Y11&15&20&-&-\\----&----&----&----&---\\&-&29&31&100\\\end{array}\\\\Calculus:\\\\\begin{array}{|c|c|c|c|c|}Year&French&Spanish&German&Total\\----&----&----&----&---\\Y10&25&9&20&54\\Y11&15&20&11&46\\----&----&----&----&---\\&40&29&31&100\\\end{array}\\\\[/tex]

20 Year10's students learn German.

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

Explanation:

Make a table that has "Year 10", "Year 11", and "Total" as the three rows.

Then you'll have the columns "French", "Spanish", "German", "Total".

In the bottom right corner is the value 100. This is the grand total of everyone surveyed.

We're told that 54 people are in Year 10, which leaves 100-54 = 46 people in Year 11.

Along the "total" column on the far right side, we'll have 54, 46, and 100 in that order from top to bottom.

--------------------------

The info that "20 of the 29 people who study Spanish in Year 11" tells we have 20 people in year 11 who study Spanish, out of 29 people who study Spanish. That leaves 29-20 = 9 people in Year 10 who study Spanish. In the "Spanish" column, we have the values 9,20,29 in that exact order from top to bottom.

Next, we'll write 31 at the bottom of the "German" column to indicate 31 people study German.

The last bit of info is that "15 Year 11 students study French". So we'll write 15 in the "year 11" row and "french" column.

--------------------------

After all that info is sorted out and entered into the table, you should end up with what is shown in figure 1 (see attached image below). Ignore figure 2 for now as we'll work our way to getting there eventually.

The variables a,b,c,d are placeholders for positive whole numbers.  

There are probably a few approaches to take, but possibly the quickest is to notice that in the second row, we can say

15+20+c = 46

c+35 = 46

c = 46-35

c = 11

We have 11 students who study German in Year 11.

Once you determine c, it helps us find b. Focus on the German column to see that

b+11 = 31

b = 31-11

b = 20

There are 20 students in Year 10 who study German. You could stop here if you want.

--------------------------

Just two more variables to go.

Along the top row, we see that

a+9+20 = 54

a+29 = 54

a = 54-29

a = 25

and along the bottom row we see that

d+29+31 = 100

d+60 = 100

d = 100-60

d = 40

Or you could note along this first column to say

a+15 = d

d = a+15

d = 25+15

d = 40

So there are a few alternative paths to take.

--------------------------

All of the sections mentioned so far only involve filling out the table that is shown below in figure 2.

To answer the question your teacher wants to ask, which is how many Year 10 students study German, well that's simply 20 students. Refer to the conclusion of the previous two sections earlier.

By this point, we just simply copy the value from the completed table. This value being of course in the "Year 10" row and "German" column.

Answer:

x-7x-34=10

-6x-34=10

Step-by-step explanation:

x=-22/3

Answer:

25

Step-by-step explanation:

Since AC is similar to CE, we can say that they have equal lengths. We are given CE, DE, and BC. To solve this, we can solve for the length of CE (equal to AC) and then subtract that from BC.

To solve for CE, we are given DE and CE. We know that DE is 1/2 of CE because D is the midpoint of CE. Therefore,

7x-1 = 1/2(10x+18)

expand

7x-1 = 5x  + 9

add 1 to both sides to separate the 7x

7x = 5x + 10

subtract 5x from both sides to separate the x

2x = 10

divide both sides by 2 to separate the x

x=5

Therefore, DE = 7(5)-1 = 34 and CE = 10(5) + 18 = 68 = AC.

Using x=5, we know that BC  = 9(5) -2 = 43

Therefore, AB = AC-BC = 68-43 = 25

D is the midpoint of CE, so if you draw a line with those three points, it'll look like C-D-E.

Since DE = 7x-1, which also means CD = 7x-1.

CD + DE = CE, so (7x-1)+(7x-1) = 10x+18.

Therefore, x = 5 and CE = 68.

Since AC is congruent to CE, AC = 68.

Assuming the point B is somewhere between AC.

Since BC = 9x-2 and x = 5, which means BC = 43.

AC - BC = AB, so 68 - 43 = 25.

Therefore, AB = 25

Answer:

1. Y+2/5y

2. y-0.32y

3. Y-2/5y

4. y+0.32y

Step-by-step explanation: