Find all the zeros of the equation
-3x^4+27^2+1200=0
if you could show yourworkthat would be great :3

Answers

Answer 1

Divide both sides by -3, and replace [tex]x^2[/tex] with [tex]y[/tex]. Then

[tex]-3x^4+27x^2+1200=0\iff y^2-9y-400=0[/tex]

Factorize the quadratic in [tex]y[/tex] to get

[tex]y^2-9y-400=(y+16)(y-25)=0\implies y=-16,y=25[/tex]

which in turn means

[tex]x^2=-16,x^2=25[/tex]

But [tex]x^2\ge0[/tex] for all real [tex]x[/tex], so we can ignore the first solution. This leaves us with

[tex]x^2=25\implies x=\pm\sqrt{25}=\pm5[/tex]

If we allow for any complex solution, then we can continue with the solution we ignored:

[tex]x^2=-16\implies x=\pm\sqrt{-16}=\pm i\sqrt{16}=\pm4i[/tex]


Related Questions

After a birthday party 1/3 of the cake was left if the cake was shared equally between 4 people what fraction did each person revive

Answers

4 people shared one third (1/3)of a cake
then mathematcally it is 1/3 divided by 4
                       solution
1/3 ÷ 4/1
we'll put the 4 upside down or turn it around
1/3 × 1/4
(1×1) ÷ (3×4)
1/12 or 0.0833333333

Solve for x 13x-7 11x+11

Answers

Answer:

answer 7.3

13x-7+11x+11=180


Step-by-step explanation:


The sum of the measures of the interior angles of the polygon below is 1800°

Answers

Answer:

False

Step-by-step explanation:

The sum of the interior angles of a regular polygon is  (n – 2)180  where n is the number of sides.   Since this is a 10 sided figure,

the sum of the interior angles is (10-2)* 180 =1440

Sweet t purchased a new pair of jeans to wear at the battle of the bands on sale at 40% off.He saved $20 what was his regular price of the jeans

Answers

If he got the jeans for 40% off he paid 60% of the cost for the jeans. With that you can setup an equation.

20 is 60% of what number

is signifies equals and of signifies multiplication

20 = 0.6*x
x = 20/.6
x = 33.33

The regular price of the jeans is $33.33

Please help: Quadratic Formula Question

Answers

Answer:

1.  b=-7

2.  c= -10

Step-by-step explanation:

The standard form for the quadratic function is

ax^2 +bx+c

so  we need to rewrite the function to be in this form

2x^2 -10 = 7x

Subtract 7x from each side

2x^2 -7x-10 = 7x-7x

2x^2 -7x-10 = 0

a =2, b= -7  c=-10

Kareem lives 4/10 of a mile from the mall. Wright to equivalent fractions that show what fration of a mile Kareem lives from the mall

Answers

Answer:

8/20 and 12/30 are equivalent to 4/10.

Step-by-step explanation:

You just have to multiply the numerator and denominator by the same number.

Brandon buys a basket of flowers for $7 before tax. The sales tax is 4%. What is the total price Brandon pays for the basket of flowers?

Answers

Answer:

$7.28

Step-by-step explanation:

We have been given that Brandon buys a basket of flowers for $7 before tax. The sales tax is 4%.

The total price that Brandon paid for the basket of flowers will be equal to 7 plus 4% of 7.

We can represent this information in an equation as:

[tex]\text{The total price that Brandon paid for the basket of flowers}=7+(\frac{4}{100}\times 7)[/tex]

[tex]\text{The total price that Brandon paid for the basket of flowers}=7+(0.04\times 7)[/tex]

[tex]\text{The total price that Brandon paid for the basket of flowers}=7+0.28[/tex]

[tex]\text{The total price that Brandon paid for the basket of flowers}=7.28[/tex]

Therefore, the total price paid by Brandon for the basket of flowers was $7.28.

Answer:

Total price Brandon pays for the basket of flowers is, $7.28

Step-by-step explanation:

As per the given statement: Brandon buys a basket of flowers for $7 before tax.

Convert this $7 into cents.

1 dollars = 100 cents.

$7 = 700 cents.

It is also given that the sales tax is 4%.

then;

Sales tax = [tex]4\% \times 700 = \frac{4}{100} \times 700 = 4 \times 7 =28 cents[/tex]

Total price Brandon pays = Price of Brandon buys a flower before tax + sales tax price

=  700 + 28 = 728 cents = $7.28

Therefore, the total price Brandon pays for the basket of flowers is, $7.28





A television normally costs $1,420. Due to a store sale, the televison is now $1,022.40. What was the percentage taken off the television?

Answers

Answer: 28%

Step-by-step explanation:

  [tex]\dfrac{new-original}{original}[/tex]

 [tex]=\dfrac{1022.40-1420}{1420}[/tex]

 [tex]=\dfrac{-397.60}{1420}[/tex]

= -0.28

= -28%


NOTE: negative sign represents decrease

Mr. Vargas is buying used computer equipment. He buys 3 keyboards and 4 mice. He spends $42. If the items are all the same price, how much does each item cost?

Answers

Answer:

Hello.

The answer is $6 each item.

Step-by-step explanation:

If all of the items are the same price, then we have a total of 7 items ( 3 keyboards + 4 mic = 7 items).

So at the end is: 7 items ÷ $42 = $6.


The cost of each item is $6.

What is Division?

A division is a process of splitting a specific amount into equal parts.

Given that Mr. Vargas is buying used computer equipment. He buys 3 keyboards and 4 mice. He spends $42.

Since, cost of each item is same, therefore total item = (3 + 4) = 7

Let the cost of each item be c,

7c = 42

c = 6

Hence, The cost of each item is $6.

For more references on division, click;

https://brainly.com/question/21416852

#SPJ2

Dan paid $34.30 for a sweater the price included a 40% markup what is the cost of the sweater before the markup

Answers

Answer:

$24.5

Step-by-step explanation:

Let x be the cost of sweater before markup.

We are told that Dan paid $34.30 for a sweater the price included a 40% markup. This means x plus 40% of x equals 34.30.

We can represent this information as:

[tex]x+\frac{40}{100}x=34.30[/tex]

[tex]x+0.40x=34.30[/tex]

[tex]1.40x=34.30[/tex]

[tex]x=\frac{34.30}{1.40}[/tex]

[tex]x=24.5[/tex]

Therefore, the cost of sweater before the markup was $24.5.

If you break up the number under the radical in the square root of 36 into two factors that are perfect squares, what are the two factors?

Answers

Answer:

6

Step-by-step explanation:

sqrt (36)

Lets break this into parts

sqrt(4 * 9)

sqrt(4)  * sqrt(9)

2 * 3

6

Pls help me with this Trig question!

Answers

Answer:

s = 65/3 pi

Step-by-step explanation:

The length of the intercepted arc is given by the formula

s =r*theta  when theta is given in radians

r = 13

theta = 5 pi/3

Substituting what we know

s = 13 * 5 pi/3

s = 65/3 pi

Since we want an exact answer, we have to leave it in terms of pi and as a fraction

The perimeter of a rectangle is 84m. The length is two and a half times the width. Find the dimensions of the rectangle. Question 5 options: Length = 30m; Width = 12m Length = 28m; Width = 70m Length = 12m; Width = 30m Length = 70m; Width = 28m

Answers

w - width

2.5w - length

84m - perimeter

w + w + 2.5w + 2.5w = 7w - perimeter

The equation:

7w = 84    divide both sides by 7

w = 12 m

length = 2.5w → 2.5w = 2.5(12) = 30 m

Answer: length = 30m; width = 12m

Jenson had 558 game cards. He lost 92 of them in a game and gave 105 game cards to his brother. How many game cards had he left ?

Answers

Answer:

After giving 197 cards away, Jenson is left with 361 cards

Step-by-step explanation:


An electric heater uses 3/5 watts power each hour. How man watts power will the heater use in a 1/2 hour

Answers

Answer: 3/10 watts


Step-by-step explanation:

3/5 converts to 6/10

6/10 / 2 = 3/10


Answer:

3/10

Step-by-step explanation:

3/5 converts to 6/10

6/10 / 2 = 3/10

The length of a base of a rectangular prism is 8 inches. The width of the prism is 4 and a half inches, and the height is 3 and a half inches. What is the volume of the prism?

Answers

volume = 4 × 8 × 3
volume =96.

Determine the equation of the hyperbola.

Answers

Answer:

A) x²/9 -y²/4 = 1

Step-by-step explanation:

The distance from center to one vertex is half the difference of the distances from a point to either focus. That is, the distance from center to the vertex is 3 on the x-axis, so the x-term is (x/3)² = x²/9.

In the picture, ...

... c² = a² + b²

The problem statement tells us c = √13, so we know c² = 13. Then ...

... b² = c² - a² = 13 -9 = 4

and the y-term is y²/4.

Thus, the equation is ...

... x²/9 - y²/4 = 1

_____

You knew that was the correct choice as soon as you knew the x-term.

Can someone help with these? 17 PT + BRainliest

Answers

Answer:

29. e = D/(3f²)

30. k=-4, x=41 . . . . matches the 2nd selection

Step-by-step explanation:

29. Multiply by the inverse of the coefficient of e. That coefficient is 3f², so you divide by that quantity.

... D = e(3f²)

... D/(3f²) = e . . . . . matches the first choice

___

30. You want to solve for k and use it with a different y-value.

... y = kx

... -96 = k·24

... -96/24 = k = -4

For y = -164, you have

... -164 = -4·x

... -164/-4 = x = 41

The coefficient of variation is -4, x is 41.

please help me out!!!!!!

Answers

1) The question is specifically asking about graduates. The total number of graduates is 2,610.

2) The total number of graduates on financial aid is 1,879.

3) So I think what you need to do is divide 2,610 (the total number of graduates) by the total of graduates on financial aid.

4) Using a calculator, I got 1.3.

Edit: I think MrBillDoesMath got it correct. But I appreciate you thanking me, despite my answer not being right.

Hello from MrBillDoesMath!

Answer:

.72

Discussion:

From the table, 1879 graduates students are receiving financial aid. Also from the table the total number of grad students is 2610. Hence the probability of a grad student receiving financial aid is   1879 /2610 = .72


Regards,  

MrB


A collection of 36 shirts and 42 jackets contains 842 buttons. A collection of 66 shirts and 77 jackets contains 137 buttons. Each shirt has the same number of buttons, and each jacket has the same number of buttons. How many buttons are there in a Fiona's Fashion shirt, and how many buttons are there in a jacket?

Answers

There are 102 shirts. There are 979 buttons in all. There are 119 jackets in all. All to there are 8 buttons in a jacket

Answer:



Step-by-step explanation:

Let x represent the number of buttons on shirts and y represent the number of buttons on jackets.

If 36 shirts and 42 jackets contain 842 buttons. This implies:

36x + 42y = 842 (1)

If 66 shirts and 77 jackets contain 137 buttons. This implies:

66x + 77y = 137 (2)

If you take the first equation: 36x + 42y = 842 and isolate the x, then you will have x = (842 - 42y) / 36

If you substitute x into the second equation:

66((842-42y)/36) + 77y = 137

→ 11(842-42y)/6 + 77y = 137

→ 11(842-42y) + 6(77y) = 137(6)

→ 9262 - 462y + 462y = 822

→ 9262 = 822 which reveals that the equations do not have a solution

If A varies inversely as the square of B, what is the effect on B if A is multiplied by 3? Please explain.

Answers

Answer:

If A is multiplied by 3, B will be reduced by a factor [tex]\frac{1}{\sqrt{3}}[/tex]

Step-by-step explanation:

Writing the inverse proportionality relationship and expressing the dependence of B on A leads to the following:

[tex]A = \frac{1}{B^2}\implies |B| = \frac{1}{\sqrt{A}}\\B'=\frac{1}{\sqrt{3A}}= \frac{1}{\sqrt{3}}\frac{1}{\sqrt{A}}=\frac{1}{\sqrt{3}}|B|[/tex]

In words, if A triples, B will decrease by a factor [tex]\frac{1}{\sqrt{3}}[/tex], or, in other words, the square of B will decrease to one third of its previous value.



MATH HELP WILL UPVOTE!!!

The function d(h)=50+45h represents the distance a family traveled, in miles, h hours after they stopped for lunch. What does the value 45 represent in this situation?

The family drove 45 miles after they stopped for lunch.

Before lunch, the family traveled at a speed of 45 mph.

After lunch, the family traveled at a speed of 45 mph.

The family drove 45 miles before they stopped for lunch.

Answers

Answer:

After lunch, the family traveled at a speed of 45 mph is the only solution that makes sense when simplifying d(h)=50+45H

Step-by-step explanation:


Answer: After lunch the family drove 45 miles per hr. HOPE THIS HELPS!




Natalie makes 2000 per month she spends 100 on credit card payments and 250 on an auto loan what is her debt to income ratio

Answers

ANSWER — 350 : 2000 or 7 : 40 (simplified version)

Solving: 100+250=350 (the loan part).

The income is given, it the amount Natalie makes per month (2000).

Simplifying: 350/50=7, 2000/50=40

Select the correct answer. Given: AD = CF BC = DE Prove: AB = EF Statement Reason 1. AD = CF given 2. AD = AB + BC + CD CF = CD + DE + EF segment addition 3. AB + BC + CD = CD + DE + EF Transitive Property of Equality 4. AB + BC = DE + EF 5. BC = DE given 6. AB = EF Subtraction Property of Equality What is the reason for the fourth statement in this proof? A. definition of collinear points B. segment addition C. Subtraction Property of Equality D. Substitution Property of Equality

Answers

Answer:


Step-by-step explanation: The answer is D- Substitution Property of Equality. I just did the test and it was right.


Answer:

C. Subtraction property of equality.

Step-by-step explanation:

Given AD= CF

 And BC=DE

To prove that AB=EF

Proof:

1.Statement: AD=CF

Reason: Given in question.

2. Statement: AD= AB+BC+ CD, CF= CD+DE+EF

Reason: Segment addition property because AB,BC,and CD are the segments of AB and CD,DE and DE are segments of CF.

3. Statement: AB+BC+CD=CD+DE+EF

Reason: Transitive property of equality

Transitive property: If ab=bc and bc=ca

Then   , ab=ca

4.Statement:  AB+BC= DE+EF

Reason: By using subtraction property of equality.

5. Statement:BC=DE

Reason: Given in question.

6. Statement: AB=EF

Reason: when we put BC=DE . Then we get AB+DE=DE+EF. By using subtraction property of equality .

Hence proved .

I need help. I have tried doing this question and none of the answers were right. Please help me.


Which ordered pairs lie on the graph of the exponential function f(x)=− 3 (x−1) +2 ? Select each correct answer.


A. (4,−25)

B. (1,  1)

C. (−1,  2)

D. (0,  0)

Answers

Answer:

A and B

Step-by-step explanation:

assuming the function should be

- [tex]3^{x-1}[/tex] + 2, then

A

substitute the x value into f(x) and check the validity of the y- value

f(4) = - [tex]3^{3}[/tex] + 2 = - 27 + 2 = - 25 ← agrees with y value

(4, - 25) lies on the graph

B f(1) = - [tex]3^{0}[/tex] + 2 = - 1 + 2 = 1 ← agrees with y value

(1, 1) lies on the graph

C

f(- 1) = - [tex]3^{-2}[/tex] + 2 = - [tex]\frac{1}{9}[/tex] + 2 ≠ 2

(- 1, 2) does not lie on the graph

D

f(0) = [tex]3^{-1}[/tex] + 2 = - [tex]\frac{1}{3}[/tex] + 2 ≠ 0

(0, 0) does not lie on the graph




The mean and standard deviation for number of robberies in the U.S. from 2000 to 2015 are x̄ = 354,718 and sx = 28,803. The mean and standard deviation for number of assaults in the U.S. for the same time period are ȳ = 774,140 and sy = 44,910. The correlation coefficient is r = 0.84. Find the equation for the least-squares regression line for number of assaults compared with number of robberies. ŷ = 309,552.15 + 1.31x ŷ = 1.31 + 309,552.15x ŷ = 546,641.84 + 0.64x ŷ = 0.64 + 546,641.84x Unable to determine the equation

Answers

Answer:

[tex]\hat{y}=309,552.15 + 1.31x[/tex]

Step-by-step explanation:

The equation for the least-squares regression is,

[tex]\hat{y}=a+bx[/tex]

where b is the slope and a is the intercept.

They can be found out by,

[tex]b=r\cdot \dfrac{SD_y}{SD_x},\\\\a=\overline{y}-b\overline{x}[/tex]

where,

r = correlation coefficient = 0.84

[tex]SD_y[/tex] = standard deviation of y = 44,910

[tex]SD_x[/tex] = standard deviation of x = 28,803

[tex]\overline{y}[/tex] = mean of y = 774,140

[tex]\overline{x}[/tex] = mean of x = 354,718

Putting the values,

[tex]b=0.84\cdot \dfrac{44910}{28803}=1.309\approx 1.31[/tex]

[tex]a=774140-(1.31\times 354718)\approx 309,552.15[/tex]

Therefore the equation is,

[tex]\hat{y}=309,552.15 + 1.31x[/tex]


Luke's turkey chili recipe calls for 1.5 pounds of ground turkey for every 6 servings. How many servings can he make if he has 5 pounds of ground turkey? Show your work.

Answers

Final answer:

Luke can make 20 servings with 5 pounds of ground turkey.

Explanation:

To determine the number of servings Luke can make with 5 pounds of ground turkey, we need to set up a proportion. The recipe calls for 1.5 pounds of ground turkey for every 6 servings. So, we can set up the proportion: 1.5 pounds / 6 servings = 5 pounds / x servings, where x represents the unknown number of servings. To solve for x, we cross multiply: 1.5 pounds * x servings = 5 pounds * 6 servings. Simplifying the equation, we get: 1.5x = 30. Dividing both sides by 1.5, we find that x = 20. Therefore, Luke can make 20 servings with 5 pounds of ground turkey.

If sin ⁡x=−1/2, and 270° *
If 180°<θ<270°, and sin⁡θ=−3/4, what is the value of sin(−θ)?

Answers

Answer:

For each of the three basic trig functions, (sin, cos, tan) there are three more which act as their reciprocals. (csc, sec, and cot respectively)


Reciprocals, of course, are flipped fractions. If you have some number x, the reciprocal can be expressed as .


An important property of reciprocals is that if you mutliply them together they will cancel out--take  for example.


Since secӨ is literally defined as the reciprocal of cosӨ, it is evident that



Read more on Brainly.com - https://brainly.com/question/505406#readmore

Step-by-step explanation:


Given the equation y − 3 = fraction 1 over 2 (x + 6) in point-slope form, identify the equation of the same line in standard form.

Answers

Answer: x - 2y = -12

Step-by-step explanation:

[tex]y - 3 = \dfrac{1}{2} (x+6)\\2(y - 3) = (2)\dfrac{1}{2}(x + 6)\\2y - 6 = x + 6\\\underline{-x +6}\quad\underline{-x + 6}\\-x + 2y = 12\\-1(-x + 2y = 12)\\x - 2y = -12[/tex]

ANSWER:

-1/2x + y = 6

ABOUT POINT SLOPE FORM:

y - Y1 = m (x - X1)Y1 & X1 is a point on the linem represents the slopeThis form allows you to identify the slope & the point on the line

ABOUT STANDARD FORM:

Ax + By = CA & B & C are integersA &B are both non - zeroThis form is good to use when wanting to find the x & y intercepts of a line

y - 3 = 1/2 (x + 6)

y - 3 = 1/2x + 3

 + 3            + 3

y = 1/2x + 6

-1/2x   -1/2x

-1/2x + y = 6


I'm not sure if my answer is correct... But please tell me if it's correct or incorrect! Thank you! :)



A hotel has 150 rooms. The charges for a double room are $270 per night and $150 per night for a single room. On a night when the hotel was completely occupied. Revenues were $33,300. Which pair of equation can be used to determine the number of double room, d and the number of single room,s,in the hotel?

Answers

Step-by-step explanation:

Let s be charges for a single room and d be charges for a double room per night.

We are told that a hotel has 150 rooms. We can represent this information as:

[tex]s+d=150...(1)[/tex]

The charges for a double room are $270 per night and $150 per night for a single room. So the charges for s single rooms will be 150s and charges for d double rooms will be 270d.

On a night when the hotel was completely occupied. Revenues were $33,300.

We can represent this information as:  

[tex]150s+270d=33,300...(2)[/tex]

Therefore, our desired pair of equations will be:

[tex]s+d=150...(1)[/tex]

[tex]150s+270d=33,300...(2)[/tex]


Answer: First equation: s+d=150; second equation: 150s+270d=33300

Step-by-step explanation: To solve the given problem we need to write two equations, the first one will express that the total number of rooms is the sum of the single rooms an the double rooms. The second equation will include the sum of the total earnings for the single and double rooms:

First equation:

s+d=150 (the single rooms and the double rooms equal 150 rooms)

second equation:

150s+270d=33300  (the sum of the single and double rooms each one of them multiplied by their prices, equals the total revenue)

To solve the equation we isolate s from the first equation:

s=150-d

and we replace it in the second one:

150(150-d)+270d=33300

solving for d:

22500-150d+270d=33300

120d=33300-22500

120d=10800

d=10800/120

d=90.

now we calculate s from the first equation:

s=150-d

s=150-90

s=60.

There are 60 single rooms and 90 double rooms.

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