Find the missing number.

____ × 7 = 91

please help me

It looks like you have to find the value of the sum,

[tex]C = \displaystyle \frac1{21\times22\times23} + \frac1{22\times23\times24} + \cdots + \frac1{200\times201\times202}[/tex]

so that the n-th term in the sum is

[tex]\dfrac1{(21+(n-1))\times(21+n)\times(21+(n+1))} = \dfrac1{(n+20)(n+21)(n+22)}[/tex]

for 1 ≤ n ≤ 180.

We can then write the sum as

[tex]\displaystyle C = \sum_{n=1}^{180} \frac1{(n+20)(n+21)(n+22)}[/tex]

Break up the summand into partial fractions:

[tex]\dfrac1{(n+20)(n+21)(n+22)} = \dfrac a{n+20} + \dfrac b{n+21} + \dfrac c{n+22}[/tex]

Combine the fractions into one with a common denominator and set the numerators equal to one another:

[tex]1 = a(n+21)(n+22) + b(n+20)(n+22) + c(n+20)(n+21)[/tex]

Expand the right side and collect terms with the same power of n :

[tex]1 = a(n^2+43n+462)+b(n^2+42n+440) + c(n^2+41n + 420) \\\\ 1 = (a+b+c)n^2 + (43a+42b+41c)n + 462a+440b+420c[/tex]

Then

a + b + c = 0

43a + 42b + 41c = 0

462a + 440b + 420c = 1

==>   a = 1/2, b = -1, c = 1/2

Now our sum is

[tex]\displaystyle C = \sum_{n=1}^{180} \left(\frac1{2(n+20)}-\frac1{n+21}+\frac1{2(n+22)}\right)[/tex]

which is a telescoping sum. If we write out the first and last few terms, we have

C = 1/(2×21) - 1/22 + 1/(2×23)

… … + 1/(2×22) - 1/23 + 1/(2×24)

… … + 1/(2×23) - 1/24 + 1/(2×25)

… … + 1/(2×24) - 1/25 + 1/(2×26)

… … + … - … + …

… … + 1/(2×198) - 1/199 + 1/(2×200)

… … + 1/(2×199) - 1/200 + 1/(2×201)

… … + 1/(2×200) - 1/201 + 1/(2×202)

Notice the diagonal pattern of underlined and bolded terms that add up to zero (e.g. 1/(2×23) - 1/23 + 1/(2×23) = 1/23 - 1/23 = 0). So, like a telescope, the sum collapses down to a simple sum of just six terms,

C = 1/(2×21) - 1/22 + 1/(2×22) + 1/(2×201) - 1/201 + 1/(2×202)

which we simplify further to

C = 1/42 - 1/44 - 1/402 + 1/404

C = 1,115/1,042,118 ≈ 0.00106994

Answer:

Cost of a play station game = $11.3

Cost of each water ride = $22.6

Step-by-step explanation:

Entrance tickets = $89.97

Royal meal = $10.85

Cost of a play station game = x

Cost of each water ride = 2x

Find the cost of a water ride

Entrance tickets = Royal meal + 1 play station game + 3 water rides

89.97 = 10.85 + 1(x) + 3(2x)

89.97 = 10.85 + x + 6x

89.97 = 10.85 + 7x

89.97 - 10.85 = 7x

79.12 = 7x

x = 79.12/7

x = 11.302857142857

Approximately to the nearest tenth

x = $11.3

Cost of a play station game = x = $11.3

Cost of each water ride = 2x

= 2(11.3)

= $22.6

Option C

Corresponding angles along parrellel lines are conguerent.

Answered by Gauthmath must click thanks and mark brainliest

Answer:

[tex]15x^2 + 8x -12[/tex]

Step-by-step explanation:

(5x+6)(3x-2)

"foil" it out

F: 5x * 3x  = 15x^2

O: 5x * -2  = -10x

I: 6*3x = 18x

L: 6 * -2 = -12

Answer:

15x² + 8x - 12

Step-by-step explanation:

(5x + 6)(3x - 2)

Each term in the second factor is multiplied by each term in the first factor, that is

5x(3x - 2) + 6(3x - 2) ← distribute both parenthesis

= 15x² - 10x + 18x - 12 ← collect like terms

= 15x² + 8x - 12

Answer:

I think it's the zero property

Step-by-step explanation:

Answer:

[tex]x = 5[/tex]

Step-by-step explanation:

Step 1:  Distribute

[tex]4x + 2 = 2(x + 6)[/tex]

[tex]4x + 2 = (2 * x) + (2 * 6)[/tex]

[tex]4x + 2 = 2x + 12[/tex]

Step 2:  Subtract 2 from both sides

[tex]4x + 2 - 2 = 2x + 12 - 2[/tex]

[tex]4x = 2x + 10[/tex]

Step 3:  Subtract 2x from both sides

[tex]4x - 2x = 2x - 2x + 10[/tex]

[tex]2x = 10[/tex]

Step 4:  Divide both sides by 2

[tex]2x / 2 = 10 / 2[/tex]

[tex]x = 5[/tex]

Answer:  [tex]x = 5[/tex]

Hi there!  

»»————-　★　————-««

I believe your answer is:  

[tex]x = 5[/tex]

»»————-　★　————-««  

Here’s why:  

⸻⸻⸻⸻

[tex]\boxed{\text{Solving for 'x'...}}\\\\4x + 2 =2(x+6)\\------------\\\rightarrow 4x + 2 = 2x + 12\\\\\rightarrow4x - 2x +2 = 2x - 2x + 12\\\\\rightarrow 2x + 2 = 12\\\\\rightarrow2x + 2 - 2 = 12 - 2\\\\\rightarrow 2x = 10\\\\\rightarrow \frac{2x=10}{2}\\\\\rightarrow \boxed{x = 5}[/tex]

⸻⸻⸻⸻

»»————-　★　————-««  

Hope this helps you. I apologize if it’s incorrect.  

Answer:

A

Step-by-step explanation:

side opposite to smallest angle is smallest=1

Hypotenuse=2

sin 30=1/2

Answer:

can you translate in english,would be better...

answer maybe wrong because of the language but stil....

9x(2+6x+1)

=9x(9x)

81x..

Answer:

32is the answer to yours questions

Answer:

The solution to above problem is 1- $45n 2- $(250+28n) 3- $(500+20n)

Step-by-step explanation:

Answer:

a. linear pair 5 & 6

b. pair of vertical angles 5 & 2

c. pair of angles that are congruent 3 & 8

Step-by-step explanation:

A linear pair of angles is formed when two lines intersect.

Vertical angles are a pair of non-adjacent angles formed by the intersection of two straight lines. In simple words, vertical angles are located across from one another in the corners of the "X" formed by two straight lines.

If two angles are complements of the same angle (or congruent angles), then the two angles are congruent. All right angles are congruent.

Answer:

this is the same quiestion i was doing if u get answer plz send me

9514 1404 393

Answer:

  after 89 years

Step-by-step explanation:

For principal p, interest rate r, and number of years t, the two account balances are ...

  a = p·e^(rt) . . . . continuous compounding

  a = p(1+r)^t . . . . annual compounding

Using the given values, we have

  3000·e^(0.07t) . . . . . compounded continuously

  20000·1.05^t . . . . . . compounded annually

We want to find t so these are equal.

  3000·e^(0.07t) = 20000·1.05^t

  0.15e^(0.07t) = 1.05^t . . . . divide by 20,000

  ln(0.15) +0.07t = t·ln(1.05) . . . . take natural logarithms

  ln(0.15) = t·(ln(1.05) -0.07) . . . . subtract 0.07t

  t = ln(0.15)/(ln(1.05) -0.07) ≈ -1.8971/-0.02121 . . . . . divide by the coefficient of t

  t ≈ 89.4 ≈ 89

The two accounts will have the same balance after 89 years.

Answer:

x = 5

<AED = <AEC = 37

Step-by-step explanation:

<AEF = <AEC (Vertical angles)

6x+7=8x-3

or, 8x-6x=7+3

or, 2x=10

or, x=5

6x+7 = 37

Answered by GAUTHMATH

Answer:

x=5

AED =37

Step-by-step explanation:

The angles are vertical angles and vertical angles are equal

6x+7 = 8x-3

Subtract 6x from each side

6x+7-6x = 8x-6x-3

7 = 2x-3

Add 3 to each side

7+3 = 2x-3+3

10 =2x

Divide by 2

10/2 =2x/2

5 =x

We want the AED = 6x+7 = 6*5+7 = 30+7 = 37

Answer: No solution

Step-by-step explanation:

-6(x - 2) + 3x = -3(x + 3) + 21

-6x + 12 + 3x = -3x - 9 + 21

Collect like terms

-6x + 3x + 3x = -9 + 21 - 12

-6x + 6x = - 9 + 9

0 = 0

In this scenario, it can be deduced that there is no solution to Kenya's equation.

Answer:

infinitely many solutions

Step-by-step explanation:

i got it right

Answer:

x         -2     3     8     13

f^-1(x)  -1    0     1        2

Step-by-step explanation:

The inverse function has the input as the output and the output as the input

x         -2     3     8     13

f^-1(x)  -1    0     1        2

Answer: C

Step-by-step explanation: In this problem, we're given a function

in the form of a chart and we're asked to find the inverse of the function.

To find the inverse of a function, we simply switch

the x and y values in each point.

In other words, the point (-1, -2) becomes (-2, -1),

the point (0, 3) becomes (3, 0), the point (1, 8) becomes (8, 1),

and the point (2, 13) becomes (13, 2).

Answer:

[tex] 3x + y = 2 [/tex]

Step-by-step explanation:

[tex] y - y_1 = \dfrac{y_2 - y_1}{x_2 - x_1}(x - x_1) [/tex]

[tex] y - 5 = \dfrac{-7 - 5}{3 - (-1)}(x - (-1)) [/tex]

[tex] y - 5 = \dfrac{-12}{4}(x + 1) [/tex]

[tex] y - 5 = -3(x + 1) [/tex]

[tex] y - 5 = -3x - 3 [/tex]

[tex] 3x + y = 2 [/tex]

Answer:

75 - 35y / 3 + 2y = -4

( 75 - 35y + 6y ) / 3 = -4 [ Taking LCM ]

( 75 - 29y ) / 3 = -4

75 - 29y = -12

29y = 75+12

29y = 87

y = 3

hope that helps ✌

5y=-2x-10

y=-2/5x-2

Rewriting the equation to slope intercept form, you get that the slope is -2/5 and the y intercept is -2. The graph that matches that is line d.

Answer:

Line D (-5,-2)

Step-by-step explanation:

I usually just use the website, demos graphing calculator.

Answer:

opposite side of an angle

hypotenuse

Answer:

1:15 minuites

Step-by-step explanation:

30 minuites

Answer:

8:30 A.M.

Step-by-step explanation:

Start by adding up the total time spent traveling.

3h 30min + 1h 30min + 1h 15 min = 5h 15 min

If she arrived in Orlando at 1:45 P.M., count back 5 h 15 min.

1:45 - 15 min = 1:30 - 5h = 8:30 A.M.

Answer:

six x squared y over 3 x y

Answer: 4x/y

Step-by-step explanation:

6x^2y. (2/3xy^2)= (6x^2y.2)/(3xy^2)= (12x^2y)/(3xy^2)= 4x/y

Answer:

Sorry if i'm wrong.

=6x² + 16x - 2

Answer:

multiplying by 100 "shifts" decimal point to the right by 2

90  

1379  

2989.4

Step-by-step explanation:

Answer:

0.9 x 100=90

13.79 x 100=1379

29.894 x 100=2989.4

​

Step-by-step explanation:

Answer:

-44, -42, -40, -38, -36

Step-by-step explanation:

"preceding" requires an indication of the direction.

but I assume the usual left to right direction. in that sense the provided 5 even numbers are directly preceding -35

Answer:

The answer would be -a

Step-by-step explanation:

In the examples,

5 + (-5) = 0

-1.33 + 1.33 = 0

THat means there will be a negative then a positive, or a positive then a negative.

INVERSE is the key word in this problem.

3(y+11) y=12

3(12+11)=?

12+11=23

3x23=69

Answer = 69

I hope this helps :)

Answer:

-8 and 3, or -3 and 8

Step-by-step explanation:

xy = -24

x - y = 11

x = y + 11

y(y + 11) = -24

y^2 + 11x + 24 = 0

(y + 8)(y + 3) = 0

y = -8 or y = -3

x = 3 or x = 8

the numbers are -8 and 3, or -3 and 8

Answer:

x=15.73292

Step-by-step explanation:

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

cos theta = adj/ hyp

cos 70 = x / 46

46 cos 70 =x

x=15.73292

Answer:

15.73

Step-by-step explanation:

cos(x) = adjacent leg / hypotenuse

cos(70) = x / 46

0.342 = x / 46

0.342 x 46 = x

x = 15.73

Answer:

20 days

Step-by-step explanation:

10kg= 10,000g

10,000g/500g= 20 days

Answer:

20 days

Step-by-step explanation:

1 kg=1000 grams

10 kg=10000 grams

10000÷500

=20 days