Which of the following has all the justifications Kelsey used to solve this equation?
(9th grade Algerbra 1)

here is your answer hope you will understand it

Answer:

$118

Step-by-step explanation:

First, find how much money you had after going to the bank:

100 + 30

= $130

Find how much money you spent at the store by subtracting 12 from 130:

130 - 12

= 118

So, you spent $118

Fred's age is 13 years

Let

Fred's age = x

Jack's age = 2x + 4

After 8 years:

= 2x + 12

Sum of their ages = Fred's age + Jack's age

59 = (x + 8) + (2x + 12)

59 = x + 8 + 2x + 12

59 = 3x + 20

59 - 20 = 3x

39 = 3x

x = 39/3

x = 13 years

Therefore, Fred's age = 13 years

https://brainly.com/question/24371832

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Explanation:

Let's square both sides and do a bit of algebra to get the following.

[tex]\sin(x) + \cos(x) = 1/5\\\\\left(\sin(x) + \cos(x)\right)^2 = \left(1/5\right)^2\\\\\sin^2(x) + 2\sin(x)\cos(x) + \cos^2(x) = 1/25\\\\\sin^2(x) + \cos^2(x) + 2\sin(x)\cos(x) = 1/25\\\\1 + 2\sin(x)\cos(x) = 1/25\\\\\sin(2x) = 1/25 - 1\\\\\sin(2x) = 1/25 - 25/25\\\\\sin(2x) = -24/25\\\\[/tex]

Now apply the pythagorean trig identity to determine cos(2x) based on this. You should find that cos(2x) = -7/25

This then means tan(2x) = sin(2x)/cos(2x) = 24/7.

From here, you'll use this trig identity

[tex]\tan(2x) = \frac{2\tan(x)}{1-\tan^2(x)}\\\\[/tex]

which is the same as solving

[tex]\tan(2x) = \frac{2w}{1-w^2}\\\\[/tex]

where w = tan(x)

Plug in tan(2x) = 24/7 and solve for w to get w = -4/3 or w = 3/4

So either tan(x) = -4/3 or tan(x) = 3/4.

If we were to numerically solve the original equation for x, then we'd get roughly x = 2.21; then notice how tan(2.21) = -1.345 approximately when your calculator is in radian mode.

Since tan(x) < 0 in this case, we go for tan(x) = -4/3

Answer:

Plot the coordinates on a graph and join them to form a triangle. After doing that, you can count the length of each triangular side and find the sum of the 3 sides. That will be your answer.

Answer:

The p is 4

Step-by-step explanation:

Answer:

9i + 2

Step-by-step explanation:

3 + 4i - 1 + 5i

=> 3 - 1 + 4i + 5i

=> 2 + 9i

=> 9i + 2

Answer:

9i + 2

Brainliest, please!

Step-by-step explanation:

(3 + 4i) - (1 - 5i)

3 + 4i - 1 + 5i

9i + 2

Answer x = 25°

In triangle ABC

Angle BAC = BCA

= 50

Because its isoceles triangle and base angles are equal.

x + x + 80 = 180

2x = 100

x = 50

Angle ACD is exterior angle so 80 + 50

= 130

Triangle ACD is also Isoceles Angle x = Angle CDA

130 + x + x = 180

2x = 50

x = 25

Answer:

4%  = 0.04

4000 = 0.04

6 years = 0.04

Step-by-step explanation:

Hope this helps!

Use distributive law

[tex]\boxed{\sf a(b+c)=ab+ac}[/tex]

Now

[tex]\\ \sf\longmapsto 2x(x-y)+3y(x-y)[/tex]

[tex]\\ \sf\longmapsto 2x^2-2xy+3xy-3y^2[/tex]

[tex]\\ \sf\longmapsto 2x^2-3y^2-2xy+3x^2[/tex]

[tex]\\ \sf\longmapsto 2x^2-3y^2+xy[/tex]

Taking common

Answer: 2x (x-y) + 3y (x-y)

             = ( x-y ) ( 2x-3y )

Answer:

119.43 cm²

Step-by-step explanation:

The shaded area (A) is calculated as

A = area of rectangle - area of circle

   = (11 × 12) - π × 2²

  = 132 - 4π

  ≈ 119.43 cm² ( to the nearest hundredth )

Answer:

an expression of more than two algebraic terms, especially the sum of several terms that contain different powers of the same variable is called polynomial. A polynomial with real coefficients is a product of irreducible polynomials of first and second degrees.

Answer:

if Q={1,3,5,7,9}Express it in description methods

Answer: With the condition that age is 30 or under, the sample space is restricted to the first column. This simplifies the problem to:

P(uses mass transit |age is 30 or under) = 125/575=0.217

Step-by-step explanation:

edmentum

Answer:

Step-by-step explanation:

According to intersecting secants theorem we have the following equation:

Solve it for k:

Step-by-step explanation:

45 >= 4x + 5

40 >= 4x

10 >= x (x <= 10)

and

53 > 4x + 5

48 > 4x

12 > x (x < 12)

so, both conditions need to be true (that is the meaning of "and").

how can that be achieved ? well, the harder, narrower condition beats any other.

so, when x <= 10, then it is automatically also smaller than 12.

so, the solution (inequality notation) is

x <= 10

and the graph just shows a line that starts at 10 (with a full, black dot at 10, as the point is included) and goes all the way to the left (to infinity and beyond ...)

Answer:

10cm

Step-by-step explanation:

Assuming the shape is a rectangle since it's already stated that it's a parallelogram, and the area is stated, we can use the Pythagorean theorem to find the length

[tex]a^{2} +b^2=c^2[/tex], where c will be the length

isolate c

[tex]c^2=a^2+b^2[/tex]

[tex]c=\sqrt{a^2+b^2}[/tex]

substitute for a and b

[tex]c=\sqrt{8^2+6^2}[/tex]

[tex]c=\sqrt{64+36}[/tex]

[tex]c=\sqrt{100}[/tex]

[tex]c=10[/tex]

take the help of the attachments.

Step-by-step explanation:

SEE THE IMAGE FOR SOLUTION..

hey, can i please get your intro? would you like to be my friend?

Myself Ojasvi

Class 8, 13

India

Answer:

21 1/6 ft

Step-by-step explanation:

Add the lengths together

12 1/2 + 8 2/3

Get a common denominator of 6

12 1/2 *3/3  + 8 2/3 *2/2

12 3/6 + 8 4/6

20 7/6

20 +6/6+1/6

21 1/6

Answer:

x = 110

y = 15

Step-by-step explanation:

AB is parallel to CD

angle B and angle D are alternate and they are equal

106-2x = 3x-4

106 + 4 = 3x - 2x

110 = x

same goes for y

7y + 13 = 10y - 32

13 + 32 = 10y - 7y

45 = 3y divide both sides by 3

15 = y

Answer:

here ,

question no. L the question is incomplete.

rest all are solved hope this helped u ☺️

Answer:

2nd option is the correct one

log|x|-f(x)+k

Answer:

The height of the triangle is four meters.

Step-by-step explanation:

We are given that the area of a triangle is 12 square meters. The base is two meters longer than the height, and we want to determine the height of the triangle.

Recall that the area of a triangle is given by:

[tex]\displaystyle A = \frac{1}{2}bh[/tex]

Since the area is 12 square meters:

[tex]\displaystyle 12 = \frac{1}{2}bh[/tex]

The base is two meters longer than the height. In other words, we can write that:

[tex]b = h + 2[/tex]

Substitute:

[tex]\displaystyle 12=\frac{1}{2}(h+2)h[/tex]

Solve for h. Multiply both sides by two:

[tex]24 = (h+2)h[/tex]

Distribute:

[tex]h^2+2h=24[/tex]

Isolate:

[tex]h^2+2h-24=0[/tex]

Factor:

[tex](h+6)(h-4)=0[/tex]

Zero Product Property:

[tex]h + 6 = 0\text{ or } h -4 =0[/tex]

Solve for each case:

[tex]h = -6\text{ or } h = 4[/tex]

Since the height cannot be negative, we can ignore the first solution.

Thus, the height of the triangle is four meters.

Answer:

1. mean-The mean is the average value of the data you collect. In statistics, you find the mean of your sample. Then you use that mean to approximate the mean of the entire population. If you want the mean of the data to be a good approximation of the mean of the entire population, your need to make sure that you collect a random sample. To find the mean, you find the sum of the data points you collected and divide it by the number of data points in the set. For example, if the data you collected was {3, 3, 6}. Then the mean would be (3 + 3 + 6) ÷ 3 = 12 ÷ 3 = 4. It's important to note that the mean does not have to be a data point in your set. You can generalize the formula as well. If you collect n data points {d1, d2, d3, … dn}, then the mean of your data set is . The Greek letter μ—pronounced "mu"—is used because the word "mean" begins with the letter "m." It is important that you divide by the number of data points in your set, n.

2. Population-A population is the entire group you want to understand. So, in a certain sense, you can think of the population as the "opposite" of the sample because a sample is not the entire population. A sample is chosen subset upon that you use to draw conclusions about the entire population.

3. Experiment-An experiment is a well-defined procedure under controlled conditions designed to gather data that tests a hypothesis. For example, you want to test the hypothesis that flowers grow faster when they are watered every other day as opposed to every day. Then you could water one set of plants every day and another set of plants every other day. What data would you collect? The height of each plant once a day. What conditions would you need to control? You would need to make sure that the groups of plants are treated the same in every other way by getting the same amount of sun and being maintained at the same temperature, etc.

4. Sample-A sample is a subset chosen from a population. In most cases, you want a random sample. Why? A random sample has the best chance of accurately representing the entire population.

5. Bais-Bias is the preference for a particular group or subset. In the example above, the bias was toward viewers who like sports. When your sample is not chosen at random, you introduce bias into your study. So, in a certain sense, a biased sample is the opposite of a random sample. Why? In a biased sample, some members of the population are more likely to be chosen than others. In a random sample, every member of the population is equally likely to be chosen. Bias may also occur in surveys. See "survey" below for more information on this type of bias.

6. Survey-A survey is the means of collecting a sample. In statistics, a survey is often a question or set of questions. It is critical that the questions, like the sample itself, be free from bias. Bias in a question tends to favor one response. As an extreme example of a biased question about colors might be, "Don't you think blue is beautiful and yellow is yucky?" An unbiased form of the question might be, "Which color do you prefer, blue or yellow?" Though careful, statisticians might be concerned about the order in which the colors are offered, so that might further simplify the question to, "What is your favorite color?" This type of question is most free from bias because it does not suggest a response and therefore does not favor a response.

7. Random-Random means free from bias. So, if you choose a random sample from a population, every member of the population has an equal chance of being chosen. It should be pointed out that this "true randomness" is an ideal which is difficult to achieve in real world experiments conducted on real world populations. That is why statisticians make every effort to ensure their samples chosen as free from bias as is possible, that is, as randomly as possible under real world conditions.

Step-by-step explanation:

It says what each of them are in each paragraph, you just need to match them up.

Hope this helps :)

Answer:

Solution

= -7 (x2 -6) +2y

= -7 ( 2*2 - 6 ) + 2 * 6

= -7 ( 4 - 6) + 12

= -7 - 2 + 12

= - 9 + 12

= 3

I hope this help u :)

sin(x+y) - sin(x-y) - 1 = cos(2x)

sin(90) - sin(x-y) - 1 = cos(2x)

1 - sin(x-(90-x)) - 1 = cos(2x)

-sin(2x-90) = cos(2x)

-1*(sin(2x)cos(90) - cos(2x)sin(90)) = cos(2x)

-1*(sin(2x)*0 - cos(2x)*1) = cos(2x)

-1*(0 - cos(2x)) = cos(2x)

-1*(-cos(2x)) = cos(2x)

cos(2x) = cos(2x)

This confirms the identity is true.

Notice that throughout this proof, I only changed the left hand side.

On the 5th line, I used the identity sin(A-B) = sin(A)cos(B)-cos(A)sin(B).

Step-by-step explanation:

sinx = p/h = 7/25

so

p = 7

h = 25

now

h^2 = p^2 + b^2

25^2 = 7^2 + b^2

or, 625 = 49 + b^2

or, 625-49 = b^2

or, 576 = b^2

or,  b = [tex]\sqrt{576}[/tex]

so, b = 24

so

cosx = b/h = 24/25

tanx = p/b = 7/24

Answer:  y = (-4/3)*sqrt(2/3)

This is the same as writing [tex]y = -\frac{4}{3}\sqrt{\frac{2}{3}}[/tex]

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Explanation:

The phrasing "where the absolute value of the slope is minimized" is an interesting way of saying "the tangent slope is 0". This is because absolute values are never negative, so the smallest it can get is 0.

Your teacher has given you

y = x^3 - 2x

which differentiates into

dy/dx = 3x^2 - 2

after using the power rule

The derivative function lets us determine the slope of the tangent. The slope is the dy/dx value. Since we want a slope of 0, we'll set 3x^2-2 equal to zero and solve for x. So you have the correct idea, but you won't involve the second derivative.

dy/dx = 0

3x^2 - 2 = 0

3x^2 = 2

x^2 = 2/3

x = sqrt(2/3)

Notice how I'm ignoring the negative version of this root. This is due to the fact that [tex]x \ge 0[/tex]

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Now plug this x value back into the original equation to find its corresponding y coordinate.

y = x^3 - 2x

y = x(x^2 - 2)

y = sqrt(2/3)*( 2/3 - 2 )

y = sqrt(2/3)*( -4/3 )

y = (-4/3)*sqrt(2/3)

Note that x = sqrt(2/3) leads to x^2 = 2/3 after squaring both sides.

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Therefore, the equation of this tangent line is y = (-4/3)*sqrt(2/3)

All horizontal lines are of the form y = k, for some constant k. This constant value is basically what number you want the horizontal line to go through on the y axis. That number would be (-4/3)*sqrt(2/3).

9514 1404 393

Answer:

  60

Step-by-step explanation:

Let m represent the mark Cheryn scored on her first quiz. Then her average is ...

  (m +76 +89)/3 ≥ 75

  m +165 ≥ 225 . . . . . . . . multiply by 3

  m ≥ 60 . . . . . . . . . . . . subtract 165

Cheryn scored a minimum of 60 marks on her first quiz.

Answer:

Jordans' age = 31 ; Anna's age = 19

Step-by-step explanation:

Given the 2 equations relating their ages

J + A = 50 → (1)

J = 12 + A → (2)

Substitute J = 12 + A into (1)

12 + A + A = 50

12 + 2A = 50 ( subtract 12 from both sides )

2A = 38 ( divide both sides by 2 )

A = 19

Substitute A = 19 into (2)

J = 12 + 19 = 31

Then Jordans' age = 31 ; Anna's age = 19

Answer:

Step-by-step explanation:

J = 12 + A equation 1

J + A = 50 equation 2

Solving equation 2

J + A = 50

A = 50 - J equation 3

Putting value of A in equation 1

J = 12 + A

J = 12 + 50 - J

Bringing like terms on one side

J + J = 12 + 50

2J = 62

J = 62/2 = 31

Putting value of J in equation 3

A = 50 - J

A = 50 - 31 = 19

Checking answer by putting values in equation 2

J + A = 50

31 + 19 = 50

50 = 50

So the age of Jordan is 31 and Anna is 19