The function C(x) = -2x2 + 38x + 40 models the sales, in hundreds of

millions of dollars, of compact discs for years since 1990.

Answers

Answer 1

Question:

Rewrite the function to reveal when sales of compact discs and $0.

Answer:

The cost in 2010 is $0

Step-by-step explanation:

Given

[tex]C(x) = -2x^2 + 38x + 40[/tex]

Required

Find x when [tex]C(x) = 0[/tex]

This gives:

[tex]C(x) = -2x^2 + 38x + 40[/tex]

[tex]-2x^2 + 38x + 40=0[/tex]

Expand

[tex]-2x^2 + 40x -2x+ 40=0[/tex]

Factorize:

[tex]-2x(x - 20) -2(x- 20)=0[/tex]

[tex](-2x - 2)(x- 20)=0[/tex]

Solve for x

[tex]-2x-2=0\ or\ x - 20 = 0[/tex]

[tex]x = -1\ or\ x = 20[/tex]

x represents time.  So, it cannot be negative.

[tex]x = 20[/tex]

20 years after 1990 is: 2010. Hence, the cost in 2010 is $0


Related Questions

help please!
Prove that,
when the values in a database are equal to each other, then the A.M, G.M and H.M equal to each other
note:
A.M=arithmetic mean
G.M=geometric mean
H.M= harmonic mean​

Answers

Answer:

See below

Step-by-step explanation:

the n number of value of x

[tex] \displaystyle x_{1},x _{2} \dots x_{n}[/tex]

let it be

[tex] \displaystyle x_{1} = x _{2} = x_{3}{\dots }= x_{n} = a[/tex]

now, the A.M of x is

[tex] \rm \displaystyle \: A.M = \frac{ x_{1} + x_{2} + \dots \dots \: + x_{n} }{n} [/tex]

since every value equal to a

substitute:

[tex] \rm \displaystyle \: A.M = \frac{ a + a + \dots \dots \: + a}{n} [/tex]

[tex] \rm \displaystyle \: A.M = \frac{ na}{n} [/tex]

reduce fraction:

[tex] \rm \displaystyle \: A.M = a[/tex]

the G.M of x is

[tex] \rm\displaystyle \: G.M =( x_{1} \times x _{2} {\dots }\times x_{n} {)}^{ {1}^{}/ {n}^{} } [/tex]

since every value equal to a

substitute:

[tex] \rm\displaystyle \: G.M =( a \times a{\dots }\times a{)}^{ {1}^{}/ {n}^{} } [/tex]

recall law of exponent:

[tex] \rm\displaystyle \: G.M =( {a}^{n} {)}^{ {1}^{}/ {n}^{} } [/tex]

recall law of exponent:

[tex] \rm\displaystyle \: G.M = a[/tex]

the H.M of x is

[tex] \displaystyle \: H.M = \frac{n}{ \frac{1}{ x_{1}} + \frac{1}{ x_{2} } {\dots } \: { \dots}\frac{1}{x _{n} } } [/tex]

since every value equal to a

substitute:

[tex] \displaystyle \: H.M = \frac{n}{ \frac{1}{ a} + \frac{1}{ a } {\dots } \: { \dots}\frac{1}{a } } [/tex]

[tex] \displaystyle \: H.M = \frac{n}{ \dfrac{n}{a} } [/tex]

simplify complex fraction:

[tex] \displaystyle \: H.M = n \times \frac{a}{n} [/tex]

[tex] \displaystyle \: H.M = a \: [/tex]

so

[tex] \displaystyle \: A.M = G.M = H.M = a[/tex]

hence,

[tex]\text{Proven}[/tex]

Answer:

What [tex]\colorbox{red}{Nayefx}[/tex]says is I say

Two thirds of the money in my pocket is 50 cents. a, what is one third of the money in my pocket​

Answers

Answer:

25 cents

Step-by-step explanation:

1.) Set up an equation you can solve from the wording of the question:

(2/3)*m = 50, where "m" represents the money in your pocket.

2.) Solve for that equation:

m = 50*(3/2) = 150/2 = 75, so now you know the money you have in your pocket is 75 cents

3.) Multiply the money you have in your pocket by 1/3 to find 1/3 of the money you have in your pocket:

75*(1/3) = 25

which of the following matrices has an inverse?

Answers

Answer: C

Step-by-step explanation:

plz answer fast today

Answers

Answer:

5 + 5 + 3 × 7

Step-by-step explanation:

Correct me if I'm wrong.

Distribute
3x(5x-5)

a) 12x^2+8x
b) 15x^2+10x
c) 12x^2-9x
d) 15x^2-15x​

Answers

Answer:

d

Step-by-step explanation:

3x times 5x equals 15x^2

3x times -5 equals -15x

---> 15x^2 - 15x

Kelly received two gift cards to her favorite store. One card was worth $25 and the other was
worth $40. She went shopping and used the cards to buy 3 shirts for $9 each and 2 skirts for
$17 each. How much gift card money did she have left?

Answers

She has $4 left
$40 + $25 = $65 in gift cards
9 x 3 shirts = $27
$17 x 2 skirts = $34
$65 - 27 - 34 = $4 left

Evaluate the expression 6 + 5 × 32 - 8.

43
11
6
91

Answers

Answer:

158

Step-by-step explanation:

All i know is that these answer choices cannot be found in the calculator

Answer:

158.....

PEMDAS

you multiply first 6+160-8

then you add or subtract

158

The blueprint for a fence shows a rectangle with the dimensions bin x
18in. The scale for the actual fence is 2in : 10ft. What is the length and
width of the actual fence?

Answers

Answer:

The width of the actual fence is 90ft

Step-by-step explanation:

If 2in = 10ft, you want to find the scale factor. To do this, you need to divide 10/2, so for every 5ft, it is 1in. Now, you would take how many inches you have and multiply it by 5. (in our case, 18in)

18 x 5 = 90.

So the actual fence length is 90ft.

Kristy dad makes 3 times as much per hour as she does. If he makes $48 per hour, how much per hour, how much per hour does kristy make

Answers

Answer:

Kristy makes 16 per hour.

Step-by-step explanation: Divded 48 by 3.

I don't know how to do this, I wasn't paying attention in class

Answers

Answer:

39.837168574084177751131265854635

Step-by-step explanation:

If you plug it into a calculator, you get that.

Next time, please pay attention in class and save us all a little trouble.

Which ordered pair is best estimate for the solution of the system of equations Y=3/2x plus 6, y equals 1/4 X -2

Answers

Answer:

x = -6.4 and y = -3.6

Step-by-step explanation:

The given system of equations are :

[tex]y=\dfrac{3}{2}x+6[/tex] ....(1)

and

[tex]y=\dfrac{x}{4}-2[/tex] ....(2)

We need to solve equation (1) and (2).

From equation (1) and (2),

[tex]\dfrac{3}{2}x+6=\dfrac{x}{4}-2[/tex]

Taking like terms together,

[tex]\dfrac{3}{2}x-\dfrac{x}{4}=-2-6\\\\\dfrac{6x-x}{4}=-8\\\\x=-6.4[/tex]

Put the value of x in equation (1).

[tex]y=\dfrac{3}{2}(-6.4)+6\\\\=-3.6[/tex]

So, the values of x and y are x = -6.4 and y = -3.6

Question 10 of 10
In a unit circle, 0 = 3pi/2 radians. What is the terminal point?
A. (0,1)
B. (1,0)
C. (-1,0)
D. (0, -1)

Answers

I think it’s D (sorry if you get it wrong)

The terminal point is (0, -1) if in a unit circle the angle is 3π/2 option (D) is correct.

What is a circle?

It is described as a set of points, where each point is at the same distance from a fixed point (called the center of a circle)

We have:

In a unit circle, θ = 3π/2 radians.

r = 1

Angle θ = 3π/2

The terminal point is (rcosθ, rsinθ)

= (cos3π/2, sin3π/2)

= (0, -1)

Thus, the terminal point is (0, -1) if in a unit circle the angle is 3π/2 option (D) is correct.

Learn more about circle here:

brainly.com/question/11833983

#SPJ5

Write the repeating rational number 0.828282… as a fraction.

Answers

Answer:

Step-by-step explanation:0.828282 = 0.828282/1 = 8.28282/10 = 82.8282/100 = 828.282/1000 = 8282.82/10000 = 82828.2/100000 = 828282/1000000

And finally we have:

0.828282 as a fraction equals 828282/1000000

Given the points A(-4,-1) B(-2,-5) C(0,1) D(2,-3)
What is the most precise name of this shape?

Answers

Trapezoid

---

hope it helps

sorry if i'm wrong

i used mental maths

Dude That's a square not a trapezoid

1/2 + 1/5 fraction model pls help!

Answers

1/2 + 1/5 = 5/10 + 2/10 = 7/10

Answer:

7/10

Step-by-step explanation:

1x5/2x5 + 1x2/5x2

=5/10+2/10

=7/10

Define: probability sample a) every possible sample of a given size has the same chance to be selected. b) the explanatory variable(s) in an experiment. c) gives each member of the population a known chance to be selected. d) successively smaller groups are selected within the population in stages. e) using extraneous factors to create similar groups. f) people who choose themselves for a sample by responding to a general appeal. g) choosing the individuals easiest to reach. h) directly holding extraneous factors constant. i) population is divided into similar groups and a SRS is chosen from each group.

Answers

Answer:

c) gives each member of the population a known chance to be selected

Step-by-step explanation:

A sample is said to be  a probability sample when each and every unit of the population would have the known chance or the probability i.e. more than zero when selected in the sample

So according to the given options, it is the sample where each member have the known chance to be selected

Therefore the option c is correct

calculate the value of x for the following polygon



(answers me or i'll throw oli london at you )​

Answers

Answer:

X = 60 degrees

Answer

80°

Step by Explanation:

the angle right to 60°= 180-60 (linear pair)

= 120°

total angle of 5 sided polygon= 540°

540° = x + 110° + 130° + 100° + 120°

540° = x + 460°

x= 540° - 460°

x = 80°

Factor the expression using the GCF.
42 – 12 =

Answers

Answer:

30

Step-by-step explanation:

Well 42

        -

       12

       30

PLEASE PLEASE PLEASE HELP
WITH 2D AND 3A ONLY, PLEASE SHOW YOUR WORKING​

Answers

Answer:

2d) d = 60°

3a) x = 50°

Step-by-step explanation:

2d) both of the diagonals pass through the centre of the circle and divide the rectangle into 4 triangles,then it means that;

30 + d = 90°

d = 90 - 30

d = 60°

3a) since O is the centre of the circle, and we can see that the 2 chords directly above and below the centre are parallel to each other, it means that angle x = 50° since the two sides projecting from the centre to form x° and 50° are equal and in essence used to form isosceles triangle.

Please help I'm begging a ACE OR GENES To help me please please help please please ASAP please please help please please ASAP please please help

Answers

Answer:

2/3

Step-by-step explanation:

the ratio of base1 ABCD to base 1 of WXYZ is        

                      8                 to      12

     8/12    = 2/3      

PLEASE HELPPPPPPPPPPPPPPPP

Answers

Answer:

Our radius is already given, 8.

8 x 3.14 x 2 = 50.24cm <-------- perimeter/circumference

8^2 x 3.14

64 x 3.14 = 200.96cm2 <------- area

Formula of a circumference:

2πr

2 x pie x radius (pie can be used as 22/7 or 3/4 most likely 3.14)

Formula of an area of a Circle:

πr^2

pie x radius squared (pie can be used as 22/7 or 3.14)

Kevin has these shirts in his closet.
• 3 blue shirts
• 5 red shirts
• 3 purple shirts
• 4 white shirts
Kevin will randomly choose one shirt, not put it back and then choose another shirt. What is the probability that he will choose a red shirt and then a white shirt?

Answers

Since there are a total of 15 shirts,

5 red shirts+4 white shirts= 9 shirts total

3 blue shirts+3 purple shirts= 6 shirts total

The odds that you would pick a red shirt and then a white are 3:2

3 being the 9 red and white shirts combined.

2 being the 6 purple and blue shirts combined.

9:6 simplified=3:2

9/3=3

6/3=2

3:2

Answer: The odds that you would pick a red shirt then a white shirt would be 3:2 or 60%

find the buying price if the selling price is 240 and profit is 20 percent​

Answers

Answer:

192

Step-by-step explanation:

You have to find 20% of 240.

So write 20% as 20 over 240 in fraction form.

[tex]\frac{20}{240}[/tex]

Since, finding the fraction of a number is same as multiplying the fraction with the number, we have

[tex]\frac{20}{100}[/tex] of 240 = [tex]\frac{20}{100}[/tex] × 240

Therefore, the answer is 48

If you are using a calculator, simply enter 20÷100×240 which will give you 48 as the answer.

Now since it  wants to know how much you paid for the goods you do 240-48=192

So since a company is selling goods with a 20% profit

That means they bought it from somewhere else

Because they had to be manufactured

It wants how much the company paid the company that manufactured the goods

I hope this helped. Some resources that are helpful to look at in case of any more confusion are:

https://answers.everydaycalculation.com/percent-of/20-240

https://www.mathsisfun.com/

https://www.ixl.com/

Good luck young mathematician!

QUESTION 4
Factorise fully:
4.1.1
12x² – x - 6​

Answers

Answer:

y = (4x - 3)(3x + 2)

Step-by-step explanation:

Factorization is the process of taking like terms out of number such that one can rewrite an expression by its factors, or as the products of serval smaller expressions.

The first step to factoring an equation is to rewrite the linear term as the sum or difference of two other linear terms. One must do this in such as way that it shares a common factor with one of the other terms in the expression.

[tex]12x^2 -x - 6[/tex]

[tex]12x^2 -9x + 8x - 6[/tex]

Take out the common factor,

[tex]3x(4x-3)+2(4x-3)[/tex]

Factor,

[tex](3x+2)(4x-3)[/tex]

8/10=6/5 what is this

Answers

Answer:

Hi! You're uspposed to check the equality, and it is false. 8/10 is not equal to 6/5.

However, If you add the two together by making the common denominator 10, you will get 20/10 or 2.

Answer:

4/5=6/5 :3

Step-by-step explanation:

Right answer will be marked brainlist .

Answers

Answer:

$1159.69

Step-by-step explanation:

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

A = 1000 (1 + 0.05/2)^2(3)

A = $1159.69

OMG PLS HELP WITH THIS IM PANICKING OMG I GOT A F IN MATH MY MOM JUST YELLED AT ME IM CRYING PLS HELP WITH THS-

Answers

Answer:

4. 50,000 square miles

5. The office would round to $800,000 instead of $700,000 because they would lose that needed $35,495. If they rounded down, their budget would be cut short, and they won’t have enough money for the office.

6. Five numbers that could also be the population: 577,777; 575,555; 578,999: 578,787; 581,545.

7. 600,000

8.584,000

9. 260,000

Step-by-step explanation:

4. In this question, we’re rounding the number, “54,555” go the nearest ten thousand. When rounding numbers you look at the number next to the digit your rounding. In this case, since the second number is not 5 or higher, we round it to 50,000 as that’s closer than 60,000.

5. Like I stated above: if they round to the lowest amount, they won’t have enough money to but what they need. Therefore, even if according to rounding it needs to be lower, it will not be beneficial to the company.

6. This are all possible numbers cause they can all by round to 580,000 AND 600,000

7. Since the number next to six is not five or higher, we round it to the closest number which is 600,000.

8. Since the number next to 3 is 5, we round it to the higher number. So it’s 584,000

9. Since the number next to the underlined nunber is 6, we round it to the closest number which is 260,000

If you have any more questions, you can ask me :)

-1.2k + 3.9 - g + .5g + 7 + .3k

Answers

Answer:

hi

Step-by-step explanation:

Use the following graph to solve the equation 3n + 7 = 52

Answers

Answer:

[tex]3n + 7 = 52 \\ 3n = 52 - 7 \\ 3n = 45 \\ n = \frac{45}{3} \\ n = 15[/tex]

Graph is not inserted.

Hopes this helps:

Answer: 15

1. Subtract 7 from both sides.
3n = 52 - 7


2. Simplify 52 - 7 to 45.
3n = 45


3. Divided both sides by 3.
N = 45/3


4. Simplify 45/3 to 15.
N = 15

Someone solve this please

Answers

Answer:

the pyramid is 80 ft² and the rectangular prism is 240 ft²

Step-by-step explanation:

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