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Answer:

160 chemistry books and 80 history books

Step-by-step explanation:

C=chemistry books sold, H=history books sold

C=2H

C+H=240, 3H=240, H=80, C=160

Answer:

=17x²-x

Step-by-step explanation:

=x.(9x²+18x-x-2)-x.(9x²-1)

=x.(9x²+17x-2-9x²+1)

=x.(17x-1)

=17x²-x

Answer:

In the sciences, many times it is necessary to be able to interpret graphs as well as be able to graph certain equations. Often data is available in a graphical format and you must be able to extract the necessary information. Other times, it may be helpful to plot an equation in order to fully understand a problem. However, graphing can be difficult for some students. The format in this section is a little different. The first part will be simply showing what some special equations look like in graphical form and the second part will be a series of questions to help you understand graphs better.

Step-by-step explanation:

Answer:

a2=12 (the second term of the sequence is 12)

Step-by-step explanation:

a5=324

If the term to term rule is multiply by any number, we deal with geometrical sequence

The formula you should use is an= a1*r^(n-1)  where n is the number of the term which we know. In our case we know

a5, so use 5 instead of n

Then you have a5=a1*r^4 where r is the number 3 (because each next term is greater than previous in 3 times)

a5=324

324= a1*3^4

324=a1*81

a1=4 (We find the first term of sequence, because having it you can easily search for every term )

Return to the formula an= a1*r^n-1

Now search for the second term using 2 instead of n in the formula

a2= a1*r^1

a2=a1*r, a1=4, r=3

a2=4*3=12

that's the answer pls mark as brainliest

Answer:

x = 71 and y = 19

Step-by-step explanation:

Given the 2 equations

x + y = 90 → (1)

x = 14 + 3y → (2)

Substitute x = 14 + 3y into (1)

14 + 3y + y = 90 ( subtract 14 from both sides )

4y = 76 ( divide both sides by 4 )

y = 19

Substitute y = 19 into (1) for value of x

x + 19 = 90 ( subtract 19 from both sides )

x = 71

Larger number x = 71 ; Smaller number y = 19

Answer: 3f

Step-by-step explanation:

Answer:

-25 > -5(x+2.5)

-25 > -5x -12.5

x > 5/2

please click thanks and mark brainliest if you like :)

Answer:

x < 2.5

Step-by-step explanation:

-25>-5(x-12.5)

-25 > -5x -12.5

add 12.5 to both sides

-25+12.5 > -5x -12.5+12.5

-12.5> -5x

divide both sides by -5

(-12.5/-5)> -5x/-5

x>2.5

since we divided by a negative,the inequality sign will flip over

x<2.5

Answer:

does it want the degree????

Answer:

Since this is a linear (non-exponential) population problem you can just use the standard y=mx+b form of an equation. Where m = (change in population/change in years)

The numbers you were provided state that over the course of 7 years (1998-1991) the population increased by 420 people (4130-3710). So, (420/7) = 60 = m. Assuming that the growth rate for 1990 is the same as 1991. then you would have a starting population of (3710-60) or 3650, that would be your "b" value since at t=0 P(t) = 3650. This yields a final equation of P(t) = 60t +3650. Check the answer at t=1 and you get the population during 1991: 3710.

Step-by-step explanation:

.

The value of the function of the surface area of a sphere when the radius is 11.5 cm is approximately 1661.9 cm²

The process of arriving at the above value is as follows;

The known parameter

The function of the radius representing the surface area of a sphere is, f(r) = A = 4·π·r²

The radius of the basketball, r = 11.5 cm

Required;

To evaluate the function, f(r), for the basketball

Method;

The process of evaluating a function, is to find the value of the function at a given value of the input or independent variable of the function

The input variable is the variable that determines the output value of the function, it is the variable which is the function is about

In the question, the function given is dependent on the radius, r

Therefore;

When r = 11.5 cm (the radius of the basketball), from the function, the surface area of the basketball, A = f(11.5) = 4 × π × (11.5 cm)² ≈ 1661.9 cm²

Therefore;

The evaluation of the function which is the value of the function, f(r) = A,

when the radius, r, is 11.5 cm, which is the surface area of the spherical

basketball, is A ≈ 1661.9 cm²

Learn more about evaluation of functions here;

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Answer:

k = 4

Step-by-step explanation:

In the equation: x² - 2x - 24

Replace the x with x + 3

(x+3)² - 2(x+3) - 24

x² + 6x + 9 - 2x - 6 -24

Let's rearrange it

x² + 6x -2x - 24 + 9 - 6

x² - 4x - 21

f(x+3) = x² - 4x - 21

The equivalent value of k from the function is k = -4

The function rule is the relationship between the input or domain and the output or range. A relation is a function if and only if there exists one value in the range for every domain value.

A function is a relation from a set of inputs to a set of possible outputs where each input is related to exactly one output.

Given data ,

Let the function be represented as A

Now , the value of A is

f ( x ) = x² - 2x - 24

Let the second function be represented as B

Now , the value of B is

f ( x + 3 ) = x² - kx - 21

On simplifying , we get

f ( x + 3 ) = ( x + 3 )² - 2 ( x + 3 ) - 24

f ( x + 3 ) = x² + 6x + 9 - 2x - 6 - 24

f ( x + 3 ) = x² + 4x - 21

So , from the equations , we get

-kx = 4x

Divide by -x on both sides , we get

k = -4

Hence , the equation is k = -4

To learn more about function rule click :

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hope this helps you understand the concept

Answer:

499

9

April 12 2021

Step-by-step explanation:

1 and 500 are the smallest and largest

12 is the highest common factor

Every 12 days they have an appointment together

Answer:

180

Step-by-step explanation:

Let x be the original weight

x* 15% = 27

.15x = 27

Divide each side by .15

.15x/.15 = 27/.15

x =180

Answer:

180 pounds

Step-by-step explanation:

W=27/15%

W=180 pounds

We know that the interior angle sum of a polygon is (n − 2) × 180°, where n is the number of sides.

Here, number of sides (n) = 12

So, interior angle sum = (n − 2) × 180°

=> interior angle sum = (12 - 2) × 180°

=> interior angle sum = 10 × 180°

=> interior angle sum = 1800°

So, the interior angle sum of this polygon is 1800°.

Hey there! I'm happy to help!

We see that the ladder reaches a height of 6m from the ground while being 2.4 m from the wall. The ratio of the height to the length from the wall is 6:2.4 which can actually just simplify to 2.5 because 6m to is 2.4*2.5.

This person is 80 cm from the ladder's base. We just saw that you can take the distance from the wall (in this case, our wall is the human as the human is touching the height) and multiply it by 2.5 to find the height of the ladder at that specific point. So let's do that.

80*2.5= 200

We are looking for meters though. Since there are 100 centimeters in a meter, this is just going to be 2 meters.

Have a wonderful day! :D

Answer:

24

Step-by-step explanation:

Volume of a cuboid = length*base*height or 4*2*3=24. The volume of this cuboid is 24.

Answer:

P(t) = 14300e^0.07t

Step-by-step explanation:

Let :

Population as a function of years, t = P(t) ;

Growth rate, r = 7%

Estimated population on year 2000 = Initial population = 14300

The given scenario can be modeled using an exponential function as the change in population is based in a certain percentage increase per period.

P(t) = Initial population*e^rt

P(t) = 14300*e^(0.07t)

P(t) = 14300e^0.07t

Where, t = number of years after year 2000.

Step-by-step explanation:

2×2×4=16

Hope it helps uß

Answer:

B.

Use eye contact and speak clearly and deliberately.

Step-by-step explanation:

let me know if you have any questions

Answer:

b

Step-by-step explanation:

because

Answer:

$310

Step-by-step explanation:

The first step is to add the costs of the textbook together :

$68.41 + $105.35 + $72.49 + $59.91 = $306.16

In order to round off to the nearest ten dollars, look at the units figure, if the number is greater or equal to 5, add 1 to the ten figure. If this is not the case, add zero. Replace the unit digit with zero

The unit digit is greater than 6, so 1 is added to the tens digit. The amount becomes $310

Answer:

9,580,000

Step-by-step explanation:

The ten thousand place is the 8

look and the thousands place which is 3

This is less than 5 so we leave the ten thousands place alone

9,583,507 becomes

9,580,000

[tex]\huge\text{Hey there!}[/tex]

[tex]\huge\textsf{9,583,507}[/tex]

[tex]\huge\textsf{= 9,600,000} \leftarrow \huge\textsf{nearest \underline{\underline{HUNDRED}} thousand}[/tex]

[tex]\huge\textsf{= 9,580,000} \leftarrow\huge\textsf{nearest \underline{\underline{TEN}} thousand}[/tex]

[tex]\large\textsf{83 is rounded to 80 because it is closer to 80 than 90. 3 is closer to}\\\large\textsf{0 than 10}[/tex]

[tex]\boxed{\boxed{\huge\textsf{Answer: \bf 9,580,000}}}\huge\checkmark[/tex]

[tex]\huge\text{Good luck on your assignment \& enjoy your day! }[/tex]

~[tex]\frak{Amphitrite1040:)}[/tex]

Step-by-step explanation:

Well talking about the practical use of Arthematic sequence or series..

i have an example..

suppose there is a highway and in most condition.. Petrol or diesel station are kept in a common distance..

now you can easily calculate or predict where the next petrol or diesel station is ..

and about Geometric sequence or series

There are many uses of geometric sequences in everyday life, but one of the most common is in calculating interest earned. Mathematicians calculate a term in the series by multiplying the initial value in the sequence by the rate raised to the power of one less than the term number. The sequence allows a borrower to know the amount his bank expects him to pay back using simple interest

and

Physicists use geometric progressions to calculate the amount of radioactive material left after any given number of half-lives of the material. During each half-life, the material decays by 50 percent.

Answer: b = 4

Step-by-step explanation:

Given

4b + 5 = 1 + 5b

Subtract 4b on both sides

4b + 5 - 4b = 1 + 5b - 4b

5 = 1 + b

Subtract 1 on both sides

5 - 1 = 1 + b - 1

[tex]\boxed{b=4}[/tex]

Hope this helps!! :)

Please let me know if you have any questions

Answer:

13.2%

or 115.2%

Step-by-step explanation:

hope it's correct. lemme know which one is correct

Answer:

f(4) =1

Step-by-step explanation:

f(1) = 10

f(n) = f(n − 1) – 3

Let n=2

f(2) = f(2 − 1) – 3 = 10-3 = 7

Let n =3

f(3) = f(3 − 1) – 3 = f(2) -3 = 7-3 = 4

Let n = 4

f(4) = f(4 − 1) – 3 = f(3) -3 = 4-3 = 1

Answer:

9

Step-by-step explanation:

f(4)=4(4-1)-3

f(4)=4(3)-3

f(4)=12-3

f(4)=9

Solve for b:

y = 0x + b

6 = 0 + b

b = 6

The answer is y = 0x + 6

Answer:

BF = |4 – 1| = 3

FC = |4 – 0| = 4

Using the Pythagorean Theorem to find BC:

BC2  =  BF2 + FC2

BC2   =  32 + 42

BC2   =  9 + 16

BC  =  sqaure root 25

BC  =  5

Step-by-step explanation:

The length of BC is 5 unit.

If ABC is a triangle with AC as the hypotenuse and angle B with 90 degrees then we have:

|AC|^2 = |AB|^2 + |BC|^2    

where |AB| = length of line segment AB. (AB and BC are rest of the two sides of that triangle ABC, AC being the hypotenuse).

We need to find the length of BC place point F at (4,4) and draw BF and FC now you have the right ∆BFC with BC as the hypotenuse find BC and FC using the coordinates of B,C, and,F then use the Pythagorean theorem to find BC.

Using the Pythagorean Theorem to find BC:

BC^2  =  BF^2 + FC^2

BC^2   =  32 + 42

BC^2   =  9 + 16

BC  =  √25

BC  =  5

So, BF = |4 – 1| = 3

FC = |4 – 0| = 4

Learn more about Pythagoras theorem here:

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Answer:

The score that they got on the IQ test is the dependent variable

Step-by-step explanation: