Mattie uses the discriminant to determine the number of zeros the quadratic equation 0 = 3x2 – 7x + 4 has. Which best describes the discriminant and the number of zeros?

The equation has one zero because the discriminant is 1.
The equation has one zero because the discriminant is a perfect square.
The equation has two zeros because the discriminant is greater than 0.
The equation has no zeros because the discriminant is not a perfect square.

Answers

Answer 1

Answer:

The equation has two zeros because the discriminant is greater than 0.

Step-by-step explanation:

3x^2 – 7x + 4

a=3   b = -7   c=4

The discriminant is

b^2 -4ac

(-7)^2 - 4(3)(4)

49 - 48

1

Since the discriminant is greater than zero, there are two real solutions

Answer 2

Answer:

The equation has two zeros because the discriminant is greater than 0.

Step-by-step explanation:

Mattie Uses The Discriminant To Determine The Number Of Zeros The Quadratic Equation 0 = 3x2 7x + 4 Has.

Related Questions

When x + y = 30 and x < 13, which of the following must be true?
y = 30
y > 17
y = 17
y < 17
y > 30

Answers

Answer:

y>17

Step-by-step explanation:

[tex]x + y = 30 \\ 13 + y = 30 \\ y = 17 \\ for \: x < 13 \\ y > 17[/tex]

Answer:

y>17

Step-by-step explanation:

x+y=30

x<13

What + 13 is 30?

17. So if x+y=30. Because x will be less than 13, y must make up the differnce by being greater than 17.

Ex: x=12

y+12=30

y=18

18 is greater than 17.

This is a great way to check because if your not sure, it elimates the other options!

Hope this helps!

please help with problem !!!

Answers

Answer:

Step-by-step explanation:

y = 2x^2 - 12x +19                Put brackets around the  1st 2 terms. Take 2

y = 2(x^2 - 6x ) + 19             Take 1/2 of the 6 square it and add inside the brackets

y = 2(x^2 - 6 + (6/2)^2) +19 Subtract 2 *9 from the 19. Express 1st 3 terms as ( )^2

y = 2(x- 3)^2 + 19 - 18

y = 2(x - 3)^2 + 1

Answers

y intercept when x = 0 is y = 19

axis of symmetry x = 3

vertex: (3,1)

Graph

graph: red

axis of symmetry: blue

y intercept, vertex: green

(2 + 6i)(8 – 9i)

Divide and simp

Answers

Answer:

70+30i

Step-by-step explanation:

5[tex]5^{56} x 5^{22} x 5^{-96}[/tex]

Answers

Answer:

[tex] \frac{ {11}^{56} }{ {5}^{18} } [/tex]

Step-by-step explanation:

[tex] {55}^{56} \times {5}^{22} \times {5}^{ - 96} [/tex]

[tex] = {55}^{56} \times {5}^{ - 74} [/tex]

[tex] = {11}^{56} \times {5}^{56} \times \frac{1}{ {5}^{74} } [/tex]

[tex] = {11}^{56} \times \frac{1}{ {5}^{18} } [/tex]

[tex] = \frac{ {11}^{56} }{ {5}^{18} } [/tex]

Classify the polynomial 5x3 + 4x - 2 by degree.

Answers

Answer:

3

Step-by-step explanation:

3 would be the degree of the polynomial since it has the highest degree.

How many solutions does the system have?








x+y=3
5x+5y=15

Answers

x=3-y

5(3-y) + 5y=15

15y-5y+5y=15

15y=15

Y= 15/15

Y= 1


X+(1)=3

X=3-1

X=2




Final answer: x=2 and y=1

Method: simultaneous equations

simplify the following​

Answers

Answer:

1) 11[tex]\sqrt{3}[/tex]

2) 2[tex]\sqrt{2}[/tex]

3) [tex]20\sqrt{3} + 15\sqrt{2}[/tex]

4) [tex]53 + 12\sqrt{10}[/tex]

5) -2

6) [tex]7\sqrt{2} - 5\sqrt{3}[/tex]

Step-by-step explanation:

1) 2[tex]\sqrt{12}[/tex] + 3[tex]\sqrt{48}[/tex] - [tex]\sqrt{75}[/tex]

=(2 × 2[tex]\sqrt{3}[/tex] )+ (3 × 4[tex]\sqrt{3}[/tex]) - 5[tex]\sqrt{3}[/tex]

= 4[tex]\sqrt{3}[/tex] + 12[tex]\sqrt{3}[/tex] - 5[tex]\sqrt{3}[/tex]

= 11[tex]\sqrt{3}[/tex]

2) 4[tex]\sqrt{8}[/tex] -2[tex]\sqrt{98}[/tex] + [tex]\sqrt{128}[/tex]

= (4 × 2[tex]\sqrt{2}[/tex]) - (2 × 7[tex]\sqrt{2}[/tex]) + 8[tex]\sqrt{2}[/tex]

= 8[tex]\sqrt{2}[/tex] - 14[tex]\sqrt{2}[/tex] +8[tex]\sqrt{2}[/tex]

= 2[tex]\sqrt{2}[/tex]

3) 5[tex]\sqrt{12\\}[/tex] - 3[tex]\sqrt{18} + 4 \sqrt{72} +2\sqrt{75}[/tex]

= 5× [tex]2\sqrt{3}[/tex] - 3×[tex]3\sqrt{2}[/tex] + 4×[tex]6\sqrt{2}[/tex] + 2×[tex]5\sqrt{3}[/tex]

= [tex]10\sqrt{3} - 9\sqrt{2} +24\sqrt{2} +10\sqrt{3}[/tex]

= [tex]20\sqrt{3} + 15\sqrt{2}[/tex]

4) [tex](2\sqrt{2} + 3\sqrt{5} )^{2}[/tex]

= [tex]8 + 12\sqrt{10} + 45[/tex]

= [tex]53 + 12\sqrt{10}[/tex]

5) [tex](1+\sqrt{3} ) (1-\sqrt{3} )[/tex]

= [tex]1 - 3[/tex]

= -2

6) [tex](2\sqrt{6} -1) (\sqrt{3} -\sqrt{2} )[/tex]

= [tex]2\sqrt{18}-2\sqrt{12} -\sqrt{3} +\sqrt{2}[/tex]

= 2×[tex]3\sqrt{2}[/tex] - 2×[tex]2\sqrt{3}[/tex] - [tex]\sqrt{3} + \sqrt{2}[/tex]

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

= [tex]7\sqrt{2} - 5\sqrt{3}[/tex]

Hope the working out is clear and will help you. :)

Step-by-step explanation:

please I solved the question in the diagram above

solve for w.
-9/7=-2/3w-1/2

Answers

Answer: [tex]w=\frac{33}{28}[/tex]

Step-by-step explanation:

To solve for w, we want to isolate w.

[tex]-\frac{9}{7}=-\frac{2}{3}w-\frac{1}{2}[/tex]            [add both sides by 1/2]

[tex]-\frac{11}{14}=-\frac{2}{3}w[/tex]                 [multiply both sides by -3/2]

[tex]w=\frac{33}{28}[/tex]

Now we know that [tex]w=\frac{33}{28}[/tex].

Answer:

[tex]\sf w=\dfrac{33}{28} \\[/tex]

Step-by-step explanation:

[tex]\sf -\dfrac{9}{7} =-\dfrac{2w}{3} -\dfrac{1}{2}[/tex]

First, take -2w/3 to the left side.

[tex]\sf -\dfrac{9}{7}+\dfrac{2w}{3} = -\dfrac{1}{2}[/tex]

Then, add 9/7 to both sides.

[tex]\sf \dfrac{2w}{3} = -\dfrac{1}{2}+\dfrac{9}{7}[/tex]

Make the denominators the same and add the fractions.

[tex]\sf \dfrac{2w}{3} = -\dfrac{1*7}{2*7}+\dfrac{9*2}{7*2}\\\\\sf \dfrac{2w}{3} = -\dfrac{7}{14}+\dfrac{18}{14}\\\\\sf \dfrac{2w}{3} = \dfrac{-7+18}{14}\\\\\sf \dfrac{2w}{3} = \dfrac{11}{14}[/tex]

Use cross multiplication.

[tex]\sf 2w*14=11*3\\\\28w=33[/tex]

Divide both sides by 28.

[tex]\sf w=\dfrac{33}{28} \\[/tex]

A prepaid phone card has a balance of $22.40 remaining. If calls are $0.035 per minute, which equation represents the number of minutes, m, you may talk using the card?

m/.035 = 22.40
22.40m = 0.035
m/22.40 = 0.035
0.035m = 22.40

Answers

Answer:

0.035m = 22.40

the ratio of boys and girls in a 4:3.If there are 20 boys, find the number of girls.​

Answers

Answer:

There are 15 girls.

Step-by-step explanation:

The ratio is 4:3, meaning there are 7 parts.

4 parts= 20 (Boys)

This means 1 part is 20 divided by 4.

1 part= 5

3 parts= Amount of girls.

3 x 5 = 15.

There are 15 girls.

Answer:

15

Step-by-step explanation:

Add:

boys : girls

     4 : 3 = 7

    20: ? = ?

Divide:

20 / 4 = 5

5 × 3 = 15

20: 15

So, there are 15 girls.

Which of the following statements best describes the relationship between
any point on an ellipse and each of its two foci?
A. The quotient of the distances to each focus equals a certain
constant.
B. The difference of the distances to each focus equals a certain
constant.
C. The sum of the distances to each focus equals a certain constant.
D. The product of the distances to each focus equals a certain
constant.

Answers

Answer:

C

Step-by-step explanation:

The sum of distances from any point on the ellipse to each foci equals a certain amount, no matter what point on the ellipse it starts from. The foci are on the major radius of the ellipse (the longer length of horizontal/vertical). The foci are of equal distance from the center, with one on each side.

If you wanted to find where the foci are using the major and minor radius, we can find that, representing the distance between the center and any foci as g,

g² = major radius² - minor radius². Then, the distance between the center and the foci is equal to g

BRAINLIST!! 20 POINTS! PLEASE HELP ILL FAIL IF I DONT PASS THIS TEST!!!
What type of counting problem is this?
How many different sums of money exist if we can choose 4 coins from any number of pennies, nickels, dimes, and quarters?
Combination without repetition
Permutation with repetition
Combination with repetition
Permutation without repetition

Answers

Answer:

the third one: Combination with repetition

Step-by-step explanation:

it says there are any number of pennies, nickels, dimes, and quarters, so there is repetition. the order doesn't matter because it asks for the different sums, so it's a combination with repetition

"How many different sums of money exist if we can choose 4 coins from any number of pennies, nickels, dimes, and quarters?" is a Combination with repetition problem.

What is combination with repetition?

A combination with repetition involves a multiset. A multiset allows elements to be repeated unlike an ordinary set.

Number of ways to select r things from n possibilities: C (n + r − 1, r)

Since he can choose any coin any number of time, repetition is there. Also, order in which coins are chosen is not important, thus it is a combination.

Therefore, the third option is correct. This is a combination with repetition problem.

Learn more about combination with repetition here

https://brainly.com/question/20401258

#SPJ2

Circle the correct term to complete the sentence: When you dilute a solution, the resulting solution has a concentration that is (increased/decreased) and the volume is (increased/decreased).

Answers

Answer:

1st option is decreased 2nd is increased

Step-by-step explanation:

Because you add a liquid to dilute a solution, it makes the solution weaker (less concentrated) you also added more liquid which would increase the volume

Answer:

decreased; increased

Step-by-step explanation:

when you dilute something you make it less concentrated by adding something else (usually water i think). so the concentration decreases while the volume increases

PLS HELP ME ON THIS QUESTION I WILL MARK YOU AS BRAINLIEST IF YOU KNOW THE ANSWER PLS GIVE ME A STEP BY STEP EXPLANATION!!
Data should be analyzed using each of the following except:
A. measures of central tendency
B. shape
C. population size
D. spread

Answers

The answer seems to be d

Estimate 2371 x1.84 divide 36.92

Answers

Answer:

Step-by-step explanation:

2371 x1.84 = 4362

4362 ÷ 36.92 = 118

the answer would be 118.1646804 but since the lowest sig fig in the question is 3 (1.84), we would have to round the answer to 3 SIG figs.

Final answer: 118

The closed form sum of

$$12 \left[ 1^2 \cdot 2 + 2^2 \cdot 3 + \ldots + n^2 (n+1) \right]$$
for $n \geq 1$ is $n(n+1)(n+2)(an+b).$ Find $an + b.$

Answers

Perhaps you know that

[tex]S_2 = \displaystyle\sum_{k=1}^n k^2 = \frac{n(n+1)(2n+1)}6[/tex]

and

[tex]S_3 = \displaystyle\sum_{k=1}^n k^3 = \frac{n^2(n+1)^2}4[/tex]

Then the problem is trivial, since

[tex]\displaystyle\sum_{k=1}^n k^2(k+1) = S_2 + S_3 \\\\ = \frac{2n(n+1)(2n+1)+3n^2(n+1)^2}{12} \\\\ = \frac{n(n+1)\big((2(2n+1)+3n(n+1)\big)}{12} \\\\ = \frac{n(n+1)\big(4n+2+3n^2+3n\big)}{12} \\\\ = \frac{n(n+1)(3n^2+7n+2)}{12} \\\\ = \frac{n(n+1)(3n+1)(n+2)}{12}[/tex]

Then

[tex]12\bigg(1^2\cdot2+2^2\cdot3+3^2\cdot4+\cdots+n^2(n+1)\bigg) = n(n+1)(n+2)(3n+1)[/tex]

so that a = 3 and b = 1.

Which is more likely when tossing two dice: a sum of 3 or a sum of 5?

Answers

Answer:

In my opinion, I think a sum of 5.

Step-by-step explanation:

Since you are tossing two dice, you will likely get a higher value than 3.

How many ways can a 3 come up ?

1  -  2

2  -  1

How many ways can a 5 come up ?

1  -  4

2  -  3

3  -  2

4  -  1

There are four ways to roll a 5, but only two ways to roll a 3.

So a sum of 5 is more likely.

PLEASE HELP ASAP THANK YOU!!! LOVE U

The fish population is decreasing at a rate of 3% per year. In 2002 there were about 1200 fish. Find the fish population in 2010. Round to the nearest whole number.

Answers

Answer:

912 lil fishies

Step-by-step explanation:

since its 3% per year, and 8 years, that's 24%. 1200 x 24% is 288, and 1200-288 is 912 lil fishies :)

hope this helps!!

brainliest is very appreciated!

Which property does the following statement illustrate? (a+b)c = (b+a)c

A: associative
B: Commutative
C: Identity
D: None

Answers

I believe the answer is b I think

She walks to her school at a distance of 800m from her house in 55 seconds. On reaching, she finds that the school is closed and comes back by car with her friend and reaches home in 25 seconds. Find her average speed in m/s

Answers

Answer:

per second she was walking 14.54m roughly and driving is 32m per second therefore the average is 23.27m/s

Step-by-step explanation:

divide both sides by 55 to get one.

divide both sides by 25 to get one

THEN

to find the average you simply add them and divide by two which is 46.54 which divided by two is roughly 23.27.

help pls How do you write 0.0000000080 in scientific notation? x 10​

Answers

Answer:

0.000000008 written as scientific notation is 8 × 10-9.

Answer:

8x10^-9

0.0000000080 is -9 integers from 0

What percent of 17 is 85?

I'm not sure if 85 is a whole number or a percentage...​

Answers

Answer: 85 is 500% of 17

Step-by-step explanation:

The question means what percent is 85 of 17

= 85/17×100

= 8500/17

= 500%

please click thanks and mark brainliest if you like :)

1. What is the basic economic problem that societies must solve?

A Who will consume the goods and services?
B How will the goods and services be produced?
C What goods and services should be produced?
D How to allocate resources in order to best satisfy the needs and wants of people.
2.
In which economic system are price signals, resulting from supply and demand forces, the only determining factor for the goods and services that the economy produces?

A a market economy
B a traditional economy
C a mixed economy
D a command economy

3.
How do property rights influence the exchange of goods and services in the market?

A Property rights determine ownership of resources among businesses, individuals, and governments.
B Property rights prevent market failures from arising in an economy.
C Property rights allow consumers' wants and needs to control the output of producers.
D Property rights prevent producers from exhibiting profit-seeking behavior.

4.A traditional economy is an economy where ____________

A economic decisions are based on price signals from supply and demand forces.
B economic decisions are based on traditions, culture, and beliefs.
C economic decisions are made by the government.
D economic decisions are made by the government for some resources and are based on supply and demand forces for others.

5. Which economy has the highest level of consumer sovereignty?

A command economy
B market economy
C mixed economy
D traditional economy

Answers

Answers

Step-by-step explanation:

1.D

2.A

3. A

4. B

5. B

Answers!

- What is the basic economic problem that societies must solve?

       - How to allocate resources in order to best satisfy the needs and wants of people.

- In which economic system are price signals, resulting from supply and demand forces, the only determining factor for the goods and services that the economy produces?

      - a market economy

- How do property rights influence the exchange of goods and services in the market?

      - Property rights determine ownership of resources among businesses, individuals, and governments.

- A traditional economy is an economy where ____________

      - economic decisions are based on traditions, culture, and beliefs.

- Which economy has the highest level of consumer sovereignty?

      - market economy

Hope this helps! :)

The quotient of 3 and a number x

Answers

Answer:

3/x

Step-by-step explanation:

Quotient is a division.

3/x

Find the volume of this cone.
Use 3 for T.
3ft
17 ft.
V = Tr2h
3
V
V ~ [?]ft?
Enter
your answer in decimal form.

Answers

Answer:

15.75 ft^3

Step-by-step explanation:

The volume of a cone is given by

V = 1/3 pi r^2 h where r is the radius and h is the height

We know the diameter is 3 so the radius is 1/2 the diameter or 3/2

The height is 7 and we will use 3 for pi

V = 1/3 (3) (3/2)^2 *7

V = 15.75 ft^3

Find the value of b.

Answers

Answer:

B

Step-by-step explanation:

The secant- tangent angle b is half the difference of the measures of the intercepted arcs , then

b = [tex]\frac{1}{2}[/tex] ( 180 - 35) = [tex]\frac{1}{2}[/tex] × 145° = 72.5° → B

Any help is appreciated (:

Answers

Answer: True

Step-by-step explanation:

The number is going down in a way that cannot be written as a straight line so it is a nonlinear.

142°
3xº + 22°
X=
degrees.

Answers

Answer:

x = 40°

Step-by-step explanation:

The 2 angles are vertical angles and are congruent , then

3x + 22 = 142 ( subtract 22 from both sides )

3x = 120 ( divide both sides by 3 )

x = 40°

Answer:

10000+1241222+24122+907979+153647612232

1

HCF of algebraic expression x square minus y square and x y minus y square. ​

Answers

Answer:

(x-y+z)(x-y-z)

Given (x²-2xy+y²) - z²

= (x-y)² - z²

/* By algebraic identity

a²-2ab+b² = (a-b)² */

=[(x-y)+z][(x-y)-z]

/* a²-b² = (a+b)(a-b) */

= (x-y+z)(x-y-z)

Therefore,

(x²-2xy+y²)-z² =(x-y+z)(x-y-z)

Step-by-step explanation:

x

2

y

2

=x×x×y×y

xy

2

=x×y×y

h.c.f=xy

2

looking for the equation, slope, and y-intercept of: (1,-3) and (0,-1)

Answers

Answer:

Equation: y = -2x - 1

Slope: -2

Y intercept: -1

Step-by-step explanation:

First, find the slope using rise over run, (y2 - y1) / (x2 - x1):

(y2 - y1) / (x2 - x1)

(-1 + 3) / (0 - 1)

2 / -1

= -2

So, the slope is -2. Plug this and a point into slope intercept form, y = mx + b, and solve for b:

y = mx + b

-1 = -2(0) + b

-1 = 0 + b

-1 = b

So, the y intercept is -1. Create the equation by plugging in the slope and b into y = mx + b:

y = mx + b

y = -2x - 1

The equation of the line is y = -2x - 1.

Answer: y=-2x-1. Slope is -2 and y int. is -1.

Step-by-step explanation:

First, you need to find the slope by using the slope formula y2-y1/x2-x1. Plug in the x and y coordinates, which simplifies as -1-(-3)/0-1, and furthermore to 2/-1, or -2. The y intercept can be found by the second point, (0,-1). Therefore, the y int. is -1.

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The number of the participants in the survey _______ 250 students for Oxford University.A. are B. was C. were D. have been31. The grass was yellow because it _______ all summer.A. does not rain B. has not rained C. had not rained D. would not rain32. Many people even wonder these days _______.A. what marriage is B. what is marriageC. what marriage was D. what was marriage33. The lights _______ out because we _______ the electricity bill.A. have gone / did not pay B. will go / did not paidC. go / would not pay D. went / had not paid34. _______ Tom Cruise's last movie? Yes, I _______ it three days agoA. Have you ever seen / saw B. Did you ever see / have seenC. Had you ever seen / would see D. Will you ever see / saw35. In the past, people _______ to the beach more often.A. have gone B. used to go C. were going D. had gone36. Soon, people _______ most of the time at home.A. will work B. are working C. have worked D. work37. I _______ a terrible accident while I _______ on the beach.A. see / am walking B. saw / was walkingC. was seeing / walked D. have seen / were walking38. After all, she _______ him since her childhood.A. knows B. knew C. was knowing D. had known39. We _______ touch since we _______ school three years ago.A. lost / have left B. have lost / leave C. have lost / left D. were losing / had left40._______ John usually watch TV at the weekend?A. Will B. Is C. Does D. Has41. I _______ there once a long time ago and _______ back since.A. was / have not been B. had been / was notC. would be / had not been D. have been / will not be42. As many as ten-million children _______ with the virus by the end of this decade.A. have been infected B. will be infectingC. had been infected D. will have been infected43. What _______ when the fire alarm _______ off?A. are you doing / will go B. have you done / would goC. were you doing / went D. will you do / are going44. _______ you send this wedding card to Peter, please?A. Will B. Do C. Did D. Had45. When Peter _______, I _______ him to your new house.A. will arrive / take B. arrives / will takeC. has arrived / am taking D. had arrive / had taken46. He ______ email before, so I ______ him how to use it.A. did not use / had shown B. had not used / showedC. has not used / showed D. was not using / will show47. Doctor Pike ______ the hospital after he ______ an uneventful evening on duty. He ______ of his day of rest.A. was leaving / has had / thought B. left / had had / was thinkingC. will leave / had / will think D. is leaving / will have / thinks48. She ______ me anything about that problem so far.A. is not telling B. does not tell C. will not tell D. has not told49. I think that everything ______ ready for the project procedure by the end of next month.A. will have been B. has been C. had been D. is What process must happen for clouds to form? 11.49 for 3 packages