a number is between 20 and 30 and is three times the sum of its digits. what is the number?

Answer:

see below

Step-by-step explanation:

y = x²-8x+ 15

Let x = -2

y = (-2)²-8(-2)+ 15

  = 4 +16 +15

   = 35

Let x = 1

y = (1)²-8(1)+ 15

     1 -8+15

   =8

The vertex is (4,-1)

Answer:

Step-by-step explanation:

y=x^2+x-30

y=x^2-(6-5)x-30

y=x^2-6x+5x-30

y=x(x-6)-5(x-6)

y=(x-5)(x-6)

Answer:

(x+6)(x-5)

Step-by-step explanation:

The product is -30 and the sum is 1.

Factors of -30 are

-1  and 30

-2 and 15

-3 and 10

-5 and 6

-5 + 6 = 1

Answer:

David had x amount of M&M's. He then ate 15 of them for snack. Now David only has 35 M&M's left. How many M&M's did David have in the beginning?

Step-by-step explanation:

Answer:

X= 20

Step-by-step explanation:

Hannah has 35 marbles. Hannah gives away 15 marbles. How many marbles does Hannah have left? Solve the equation X- 15=35.

Answer:

i got (-10/7, -44/7)

Answer:

The expected dollar value for a person playing this game is -$1, that is, a loss of $1.

Step-by-step explanation:

Expected dollar value:

Probability of each outcome multiplied by it's monetary outcome.

Outcomes:

45% probability of winning $100.

45% probability of losing $100.

10% probability of losing $10.

What is the expected dollar value for a person playing this game?

[tex]E = 0.45*100 - 0.45*100 - 0.1*10 = -1[/tex]

The expected dollar value for a person playing this game is -$1, that is, a loss of $1.

Answer:

B = 31.6

Step-by-step explanation:

Since this is a right triangle, we can use trig functions

tan B = opp / adj

tan B = 28.2 / 45.8

taking the inverse tan of each side

tan ^ -1 ( tan B) = tan ^-1 (28.2/45.8)

B =31.62145

Rounding to the nearest tenth

B = 31.6

Answer:

The tank can hold water 172,857.14 cubic feet

Step-by-step explanation:

Given that the shape is cylindrical, the amount of water it can hold may be determined using the formula for the volume of a cylinder.

The volume V of a cylinder whose base radius r and height is h is given as

V = Pir^2h where Pi is 22/7

Given that the height of the tank is 88 feet and the radius is 25 feet, then the volume V

= 22/7 * 25^2 *88

=  172,857.14 cubic feet

Answer:

Graph B

Step-by-step explanation:

Hope this helps

Answer:

45 mph

251 ft

Step-by-step explanation:

[tex] s = \sqrt{30fl} [/tex]

a.)

[tex] s = \sqrt{30(0.85)(80)} [/tex]

[tex] s = \sqrt{2040} [/tex]

[tex] s = 45 [/tex]

Answer: 45 mph

b.)

[tex] 80 = \sqrt{30(0.85)l} [/tex]

[tex] 80^2 = (\sqrt{25.5l})^2 [/tex]

[tex] 25.5l = 6400 [/tex]

[tex] l = 251 [/tex]

Answer: 251 ft

Answer:

x = 81°

Step-by-step explanation:

Refer to the attachment for the steps.~

Answer:

Question 1)

Cristina is traveling 11 miles per hour and Kori is traveling 20 miles per hour.

Question 2)

Four hours.

Question 3)

Paige spent two hours biking and six hours walking.

Step-by-step explanation:

Question 1)

Let Cristina's speed be x.

Kori travels 9 miles per hour faster than Cristina. So, Kori's speed is (x + 9).

After six hours, Cristina would have traveled 6x miles and Kori would have traveled 6(x + 9) miles.

Since Kori traveled in the opposite direction, we can place a negative to represent this. So, after six hours, Kori is -6(x + 9) miles away from the restaurant while Cristina is 6x miles away from the restaurant.

Since the distance between them is 186 miles, the difference of the two expressions is 186. Hence:

[tex](6x)-(-6(x+9))=186[/tex]

Distribute:

[tex]6x-(-6x-54)=186[/tex]

Distribute:

[tex]6x+6x+54=186[/tex]

Simplify:

[tex]12x=132[/tex]

Hence:

[tex]x=11[/tex]

Cristina's speed is 11 miles per hour. Thus, Kori's speed is 20 miles per hour.

Question 2)

Let h represent the amount of time that has passed in hours.

Carrie left the restaurant traveling 12 miles per hour.

Four hours later, Leah left traveling in the same direction at 24 miles per hour.

After four hours, Carrie would have traveled 12(4) = 48 miles.

Carrie would still be traveling at 12 miles per hour. So, her distance from the restaurant is given by:

[tex]12h+48[/tex]

Since Leah just left and is traveling at a rate of 24 miles per hour, her distance from the restaurant is given by:

[tex]24h[/tex]

Leah will catch up when the two expressions are equivalent. Hence:

[tex]12h+48=24h[/tex]

Solve for h:

[tex]12h=48\Rightarrow h=4[/tex]

Leah will catch up with Carrie in four hours.

Question 3)

Let x represent the amount of hours spent biking and y represent the amount of hours spent walking.

The total trip to the mall took eight hours. Hence:

[tex]x+y=8[/tex]

The mall is a total of 46 miles away. Since Paige bikes at a rate of 8 miles per hour and walks at a rate of five miles per hour:

[tex]8x+5y=46[/tex]

Solve the system. We can use elimination. Multiply the first equation by -5:

[tex]-5x-5y=-40[/tex]

We can add this to the second equation:

[tex]3x=6[/tex]

Hence:

[tex]x=2[/tex]

Using the first equation again:

[tex](2)+y=8\Rightarrow y=6[/tex]

So, Paige spent two hours biking and six hours walking.

Answer:

y=-1x+5

Step-by-step explanation:

Answer:

x+113=180

Step-by-step explanation:

it's because of parallelogram property that opposite sides are parallel so being parallel this indicates co interior angle and it's sum is 180 so ,x+113=180,x=180_113,x=67 ans

Answer:

90% confidence interval is ( -149.114, -62.666   )

Step-by-step explanation:

Given the data in the question;

Sample 1                                Sample 2

x"₁ = 259.23                            x"₂ = 365.12

s₁  = 34.713                              s₂ = 48.297

n₁ = 5                                       n₂ = 10

With 90% confidence interval for μ₁ - μ₂ { using equal variance assumption }

significance level ∝ = 1 - 90% = 1 - 0.90 = 0.1

Since we are to assume that variance are equal and they are know, we will use pooled variance;

Degree of freedom DF = n₁ + n₂ - 2 = 5 + 10 - 2 = 13

Now, pooled estimate of variance will be;

[tex]S_p^2[/tex] = [ ( n₁ - 1 )s₁² + ( n₂ - 1)s₂² ] / [ ( n₁ - 1 ) + ( n₂ - 1 ) ]

we substitute

[tex]S_p^2[/tex] = [ ( 5 - 1 )(34.713)² + ( 10 - 1)(48.297)² ] / [ ( 5 - 1 ) + ( 10 - 1 ) ]

[tex]S_p^2[/tex] = [ ( 4 × 1204.9923) + ( 9 × 2332.6 ) ] / [  4 + 9 ]

[tex]S_p^2[/tex] = [ 4819.9692 + 20993.4 ] / [  13 ]

[tex]S_p^2[/tex] = 25813.3692 / 13

[tex]S_p^2[/tex] = 1985.64378

Now the Standard Error will be;

[tex]S_{x1-x2[/tex] = √[ ( [tex]S_p^2[/tex] / n₁ ) + ( [tex]S_p^2[/tex] / n₂ ) ]

we substitute

[tex]S_{x1-x2[/tex] = √[ ( 1985.64378 / 5 ) + ( 1985.64378 / 10 ) ]

[tex]S_{x1-x2[/tex] = √[ 397.128756 + 198.564378 ]

[tex]S_{x1-x2[/tex] = √595.693134

[tex]S_{x1-x2[/tex] = 24.4068

Critical Value = [tex]t_{\frac{\alpha }{2}, df[/tex] = [tex]t_{0.05, df=13[/tex] = 1.771  { t-table }

So,

Margin of Error E =  [tex]t_{\frac{\alpha }{2}, df[/tex] × [ ( [tex]S_p^2[/tex] / n₁ ) + ( [tex]S_p^2[/tex] / n₂ ) ]

we substitute

Margin of Error E = 1.771 × 24.4068

Margin of Error E = 43.224

Point Estimate = x₁ - x₂ = 259.23 - 365.12 = -105.89

So, Limits of 90% CI will be; x₁ - x₂ ± E

Lower Limit = x₁ - x₂ - E = -105.89 - 43.224 = -149.114

Upper Limit = x₁ - x₂ - E = -105.89 + 43.224 = -62.666

Therefore, 90% confidence interval is ( -149.114, -62.666   )

Answer:

1979

91%

Step-by-step explanation:

Given the relation :

P = (318t + 6792) / (1.19t + 107.36)

P = % of household with PC

t = years since 2000

1.) We need to find t, when P = 85%

P = 0.85

0.85 = (318t + 6792) / (1.19t + 107.36)

0.85(1.19t + 107.36) = (318t + 6792)

1.0115t + 91.256 = 318t + 6792

Collect like terms :

1.0115t - 318t = 6792 - 91.256

−316.9885t = 6700.744

t = 6700.744 / - 316.9885

t = - 21.138760

t = - 21 years

2000 - 21 years = 1979

Percentage who had computer in 2014

t = 2014 - 2000 = 14

P = (318(14) + 6792) / (1.19(14)+ 107.36)

P = (4452 + 6792) / (16.66 + 107.36)

P = 11244 / 124.02

P = 90.6627

P = approximately 91%

There is no solution.

Step-by-step explanation:

Given:

y = 2x + 1

4x - 2y = 4

Substitute y = 2x + 1 into 4x - 2y = 4

4x - 2(2x + 1) = 4

4x - 4x - 2 = 4

0x = 4 + 2

0x = 6

Anything to the multiple of zero is zero. Hence 0x = 0, and 0 ≠ 6

So there is no solution to the equation.

Answer:

A = $29,201.97

A = P + I where

P (principal) = $20,000.00

I (interest) = $9,201.97

Step-by-step explanation:

First, convert R as a percent to r as a decimal

r = R/100

r = 9.5/100

r = 0.095 rate per year,

Then solve the equation for A

A = P(1 + r/n)nt

A = 20,000.00(1 + 0.095/12)(12)(4)

A = 20,000.00(1 + 0.007916667)(48)

A = $29,201.97

Summary:

The total amount accrued, principal plus interest, with compound interest on a principal of $20,000.00 at a rate of 9.5% per year compounded 12 times per year over 4 years is $29,201.97

Answer:

[tex]midpoint = ( \frac{8 + 3}{2} , \: \frac{5 + 7}{2} ) \\ = ( \frac{11}{2} , \: \frac{12}{2} ) \\ = (5.5, \: 6)[/tex]

Answer:                                                                                                                                                      

2                                                                                                                                                       Step-by-step explanation:

in the places there is X you put -3 , -3 squared minus 7 is equal to 9 , 9-7 is equal to 2

Answer:

[tex] \large{ \tt{❃ \: EXPLANATION}} : [/tex]

[tex] \large{ \tt{❁ \: LET'S \: START}} : [/tex]

[tex] \large{ \tt{⋆ \: f( - 3) = {( - 3)}^{2} - 7}}[/tex]

[tex] \large{ \tt{↦ \: f( - 3) = ( - 3) \times ( - 3) - 7}}[/tex]

[tex] \large{ \tt{↦f( - 3) = 9 - 7}}[/tex]

[tex]↦ \large{ \tt{f( - 3) = \boxed{ \tt{2}}}}[/tex]

[tex] \tt{✺ \: COMFORT \: IS \: THE \: ENEMY \: OF \: ACHIEVEMENT\: ♪}[/tex]

♡ Hope I helped! ♕

☃Have a wonderful day / evening ! ☼

# StayInAndExplore ! ☂

▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁

Answer: t = 5

Step-by-step explanation:

If 2t = 10, then we divide 10 by 2. The answer is 5.

Answer:3

Step-by-step explanation:

Answer:

37.1666666667

Step-by-step explanation:

brainiest please

Cora, her sister, and four friends. So there are 6 people, 120 candies are divided equally in the bag, so each person gets 20 candies

Each person will get 20 candles.

The division is one of the four basic mathematical operations, the other three being addition, subtraction, and multiplication.

Now it is given that,

Number of candles in the bag = 120

Cora, her sister, and four friends are going to share.

So, Number of person = 6

Thus, candles each person gets = Number of candles in the bag / Number of person

⇒ candles each person gets = 120 / 6

⇒ candles each person gets = 20

Thus, each person will get 20 candles.

To learn more about Division :

brainly.com/question/28032495

#SPJ2

Answer:

depends on the tax percentage

Step-by-step explanation:

Hope this answer helps you.

Have a great day

Mark brainliest

Answer:

the awnser is 124 YW:)

Step-by-step explanation:

62x2=124

Answer:

124 / C

Step-by-step explanation:

The angles of a triangle add up to 180 degrees.  We know that angle k is 62, angle J is 90, that adds to 152.  180-152 gives us the third angle of the triangle as 28.  Assuming that the two triangles are similar, the angle opposite of the 28 degree is also 28 degrees.  The angles on the line should also add up to 180 degrees.  So 180 - 28 - 28 = 124.

Answer:

A and E

Step-by-step explanation:

answer

A. - ( -13) = 13

thank. u

Answer:

b

Step-by-step explanation:

A is incorrect cause it would be a negative

C would also be a negative

D is a positive

so yea