when would you write an x in an equation?)

Answers

Answer 1

Answer:

[tex]\Large \boxed{\mathrm{When \ a \ number \ is \ not \ known}}[/tex]

Step-by-step explanation:

For example, a sum of a number and 6 is 12.

The number is unknown.

Let the number be x.

x + 6 = 12

We can solve for x (unknown number). Subtract 6 from both sides of the equation.

x = 6

Related Questions

Use mathematical induction to prove the statement is true for all positive integers n. 8 + 16 + 24 + ... + 8n = 4n(n + 1)? Please show work

Answers

Answer:

The sum of the series is Sₙ = n/2 [2·a + (n - 1)·d] where a = 8 and d = 8, therefore 8 + 16 + 24 + ... + 8·n = 4·n·(n + 1)

Step-by-step explanation:

The parameters given are;

8 + 16 + 24 + ... + 8·n = 4·n·(n + 1)

The given series of numbers can be checked to find;

16 - 8 = 24 - 16 = 8

Therefore, the series of numbers is an arithmetic progression with first term = 8, and common difference = 8, we have;

The sum of n terms of an arithmetic progression, Sₙ, is given as follows;

Sₙ = n/2 [2·a + (n - 1)·d]

Where;

a = The first term of the series of numbers = 8

d = The common difference = 8

∴ Sₙ = n/2 × [2×8 + (n - 1)×8] = n [2×8/2 + (n - 1)×8/2]  =  n × [8 + (n - 1)×4]

Sₙ =  n × [8 + (n - 1)×4] =  n × [8 + 4·n - 4] = n × [8  - 4 + 4·n] = n × [4 + 4·n]

Sₙ =n × [4 + 4·n] = 4 × n×(n + 1) = 4·n·(n + 1).

Luis, Diego, and Cecil are going fishing.
Luis brings 4 cans of worms. Diego brings
3 cans of worms plus 2 extra worms. Cecil
brings 2 cans of worms. If they have a
total of 65 worms and each can contains
the same number of worms, how
many worms are in each can?

Answers

Answer:

7

Step-by-step explanation:

If we call the number of worms in a can x, we can write:

4x + 3x + 2 + 2x = 65

9x + 2 = 65

9x = 63

x = 7 worms

el deposito de gasolina en una estacion de servicio alcanza para 5 dias si se venden 1400 galones diarios ¿cuantos galones diarios deben venderse para que el deposito cura 7 dias?

Answers

Answer:

u should put this also in English then type it in so it will translate

The function f(x) = 50(0.952)x, where x is the time in years, models a declining feral cat population. How many feral cats will there be in 9 years?

Answers

Answer: B) 32

Work Shown:

f(x) = 50(0.952)^x

f(9) = 50(0.952)^9

f(9) = 32.1146016801717

f(9) = 32 approximately

Side note: the exponential function is in the form a*b^x with b = 1+r = 0.952, which solves to r = -0.048. The negative r value means we have a 4.8% decrease each year.

Another note: you don't even need to use math to answer this question. Note how 50 is the starting population and the population is declining. Only choice B has a value smaller than 50, so we can rule out the others right away.

Answer:

  32

Step-by-step explanation:

The initial value of the population is f(0) = 50(0.952^0) = 50. If the population is declining, it must be less than 50 in 9 years. The only answer choice that is less than 50 is ...

  about 32 feral cats

_____

You can evaluate f(9) to choose the same answer:

  f(9) = 50(0.952^9) ≈ 32.114 ≈ 32

Euphrosynelight needs 2x-7 while her friend needs 5x+2 how much in total

Answers

Answer:

7x-5

Hope this helped; mark brainliest if it did! :)

how do you find the area of an open cylinder... what is the Formula?? please help​

Answers

Answer:

Cylinder has a formula

π×r²×h

so of it is open

π×r²×h - π×r²

Answer:

pls give brainiest

Step-by-step explanation:

A=2πr×h(r+h)

Elena drank 3 liters of water yesterday. Jada drank 3⁄4 times as much water as Elena. Lin drank twice as much water as Jada. Did Lin drink more or less water than Elena? Group of answer choices

Answers

Answer:

Lin drank more water

Step-by-step explanation:

Given

Elena = 3 litres

Jada = ¾ of Elena

Lin = 2 times of Jada

Required

Determine if Lin drank more or less water than Elena

First, we have to get the actual amount of water Jada drank.

Jada = ¾ of Elena

Substitute 3 litres of Elena

[tex]Jada = \¾ * 3 litres[/tex]

[tex]Jada = 9/4 litres[/tex]

[tex]Jada = 2\¼\ litres[/tex]

Lin = 2 * Jada

Substitute 2¼ litres for Jada

[tex]Lin = 2 * 2\¼\ litres[/tex]

[tex]Lin = 2 * 9/4 litres[/tex]

[tex]Lin = 9/2 litres[/tex]

[tex]Lin = 4\frac{1}{2} litres[/tex]

Recall that Elena drank 3 litres

Comparing 3 Litres to [tex]4\frac{1}{2}[/tex] litres, we can conclude that Lin drank more water.

what’s the equation of line ?
y =__x + __

Answers

Answer:

y=3/4x-2

Step-by-step explanation:

two points from graph (0-2) and (8,4)

find slope m: y2-y1/x2-x1

m=4+2/8-0

m=6/8=3/4

x=0 then y=b=-2

y=3/4x-2

Solve for b. -11b+7 = 40 b=

Answers

Answer:

B= -3

Step-by-step explanation:

Move the terms that do not contain b to the right then solve. Hope this helps!

Answer:

[tex]\large \boxed{{b=-3}}[/tex]

Step-by-step explanation:

[tex]-11b +7=40[/tex]

Subtract 7 from both sides.

[tex]-11b +7-7=40-7[/tex]

[tex]-11b=33[/tex]

Divide both sides by -11.

[tex]\displaystyle \frac{-11b}{-11} =\frac{33}{-11}[/tex]

[tex]b=-3[/tex]

A rectangle's length and width are in a ratio of 3:1. The perimeter is 72 inches. What are the length and width?

Answers

Answer:

Step-by-step explanation:

If the sides exist in a ratio to one another, then when you multiply some number x by both the length and the width, they still remain as a ratio. The length will be 3x and the width will be 1x. The perimeter formula is

P = 2L + 2W and since our perimeter is 72 and we have both the length and the width, we can fill in the formula and solve for x:

72 = 2(3x) + 2(1x) and

72 = 6x + 2x and

72 = 8x so

9 = x.

If x = 9, then 1x = 9 and 3x = 27. Let's check the perimeter against those side lengths.

P = 2(3x) + 2(1x) and

P = 2(27) + 2(9) and

P = 54 + 18 so

P = 72

and you're done! (The bold numbers above are the width and length, respectively.)

3/v=2/4? i need help plz

Answers

Answer:

v = 6

Step-by-step explanation:

3/v = 2/4

We can use cross products to solve

2v = 3*4

2v = 12

Divide each side by 2

2v/2 = 12/2

v =6

Answer:

v=6

Step-by-step explanation:

If this is making them equal, then you should know that 2/4 is 1/2 , so you could just multiply 3 by both the 1 and the 2 in 1/2 and 1 times 3 is 3 which is what we have and 2 times 3 is 6 which is v.

In the Rhombus, m<3=80. Find m<2

160
80
50
40

Answers

Answer: C. 50

==============================================

Explanation:

The diagonal cuts the rhombus into two congruent isosceles triangles. We know they are isosceles because the non-diagonal sides are equal in length (since all four sides of a rhombus are the same length).

Let x be the measure of angle 1. This is one base angle. The other base angle is also x as well. The third angle of the bottom triangle is angle 3, which is given to us at 80 degrees. For any triangle the three angles always add to 180.

x+x+80 = 180

2x+80 = 180

2x = 180-80

2x = 100

x = 100/2

x = 50

Angle 1 is therefore 50 degrees.

Angle 2 is also 50 degrees because angles 1 and 2 are congruent alternate interior angles. Any rhombus is a parallelogram (but not the other way around) so the top and bottom lines of the rhombus are parallel, allowing the alternate interior angles to be congruent.

Answer:

m<2 = m<1 = 50°

Step-by-step explanation:

In a Rhombus, Diagonals intersect at 90° as well bisect angles.

Therefore, in a triangle formed by <1, 90° at the diagonal intersection and angle bisection of <3 = 40°.

m<1 = m<2 = 50°

Which professionals most directly use geometry in their work? A. accountants B. astronomers C. judges D. pharmacists E. politicians\

Answers

Answer:

Astronomers directly use geometry in their work rather than accountants , judges, pharmacist and politicians.

They used geometry to measure velocity , direction, distance, relativity, momentum, and probability. They used it to look at objects in the sky with a telescope by setting a required angle to get a proper view .

But Accountants, judges, pharmacist and politicians are not in use of geometry directly or frequently.

Hence, Option 'B' is correct.

Step-by-step explanation:

Answer: b

Step-by-step explanation:


please i need help asap lol

A baseball league is holding registration for both a men's league and a women's league. Only a total of 546 players can register, and each team consists of exactly 13 players. If 25 women's teams have already registered, which inequality could be used to find m, the number of men's teams that can register? A. 25(13) + 13m 546 C. 25(13 + 13m) 546

Answers

Answer:

546 - 25 x 13 (divided by) 13

546 - (25 x 13) / 13

Step-by-step explanation:

25 x 13 = 325

546 - 325 = 221

221 / 13 = 17

17 mens teams can register.

Answer:

[tex]25(13)+13m\leq 546[/tex]

A

Step-by-step explanation:

Each team can only consists of thirteen players. Therefore, by letting w represent the number of women's teams and m the number of men's teams, the total number of players is represented by the equation:

[tex]13w+13m[/tex]

The total number of players cannot surpass 546. In other words, it must be less than or equal to. Therefore:

[tex]13w+13m\leq 546[/tex]

We are given that that 25 women's teams have already signed up. To find out the possible number of men's teams that can sign up, we can substitute 25 for w and then solve for m.

Therefore:

[tex]25(13)+13m\leq 546[/tex]

In conclusion, the answer is A.

can you solve;
3/7+5/21

Answers

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[tex]\frac{3}{7}+\frac{5}{21}[/tex]

[tex]= \frac{3}{7}+\frac{5}{21}[/tex]

[tex]= \frac{9}{21}+\frac{5}{21}[/tex]

[tex]= \frac{9 + 5}{21}[/tex]

[tex]= \frac{14}{21}[/tex]

[tex]= \frac{2}{3}[/tex] (Decimal: 0.666667)

Answer : [tex]\boxed{\frac{2}{3} }[/tex] (Decimal: 0.666667)

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        Have a great day/night!

                   ❀*May*❀

3/7+5/21=2/3

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21

For the 1st fraction, since 21 × 1 = 21,
5
21
=
5 × 1
21 × 1
= 5/21

Likewise, for the 2nd fraction, since 7 × 3 = 21,
3
7
=
3 × 3
7 × 3
= 9/21

Add the two fractions:
5
21
+
9
21
=
5 + 9
21
= 14/21

Simplify and get 2/3

line passing through points (-4,2) and (0,3)

Answers

Answer:

y-y1=m(x-x1)

or,y-2=1/4(x+4)

or,4y-8=x+4

or,x-4y+12=0 is the required equation.

Step-by-step explanation:

If it helps you, plz mark it as brainliest

Figure ABCD is a rectangle Find the value of x

Answers

Step-by-step explanation:

Since this is a rectangle these two equations for the length have to equal each other.

2x+4=7x-1

We now need to get all of the x's on one side and constant numbers on the other side.

add 1 to both sides and subtract 2x from both sides.

5=5x

divide 5 from both sides.

x=1

Some time ago , Keith's height and his nephew's height were at a ratio of 15:7. Then, Keiths height increased by 16% and his nephew,s height doubled. Keith is now 34 cm taller than his nephew, what is their total current height

Answers

Answer:

The answer is below

Step-by-step explanation:

The ratio of Keith's height and his nephew's height is 15:7. Let keith height be x cm and his nephews height be y cm.

[tex]\frac{x}{y}=\frac{15}{7} \\x=\frac{15}{7}y[/tex]

Keiths height increased by 16% , therefore Keith new height is (100% + 16%) × x = 1.16x

The nephew height is doubled, therefore his new height is 2y.

Given that Keith is now 34 cm taller than his nephew

1.16x = 2y + 34

but x = (15/7)y

[tex]1.16(\frac{15}{7} )y=2y+34\\\\\frac{87}{35} y=2y+34\\\\\frac{87}{35} y-2y=34\\\\\frac{17}{35}y=34\\ \\y=\frac{34*35}{17}\\ \\y=70\ cm[/tex]

The nephews new height = 2y = 2(70) = 140 cm

Keith new height = 2y + 34 = 140 + 34 = 174 cm

Their total current height = 140 cm + 174 cm = 314 cm

A researcher wants to use a confidence interval to estimate the proportion of college students in his state who plan to vote in the 2020 presidential election. He plans to randomly sample 120 college students, and plans to construct a 95% or 99% confidence interval. Which of these confidence intervals will be wider, and why

Answers

Answer:

99% confidence interval will be wider because as the level of confidence increase the width increases as well and the standard error decreases

Step-by-step explanation:

The  confidence interval is directly proportional to the sample size  hence the 99% confidence interval will be wider than the 95% confidence interval of the sample of 120 college students

using a 99% confidence interval gives a more accurate result than a 95% confidence because the standard error decreases with increase in confidence interval

I need help pls will give you five stars and a big thank you comrade

Answers

Answer:

B, f(x) = ( x+2) ^2(x-1) (x+3)

Step-by-step explanation:

Looking at the x- intercepts, the line passes at 2, -1, and 3, so B is you answer (:

Two mechanics worked on a car. The first mechanic worked for hours, and the second mechanic worked for hours. Together they charged a total of . What was the rate charged per hour by each mechanic if the sum of the two rates was per hour?

Answers

Answer:

The rate charged by first mechanic per hour= x =$85

The rat charged by second mechanic per hour =y = $70

Step-by-step explanation:

Two mechanics worked on a car. The first mechanic worked for 10 hours, and the second mechanic worked for 15 hours. Together they charged a total of $1900. What was the rate charged per hour by each mechanic if the sum of the two rates was $155 per hour?

Solution

Let

x= hourly rate of the first mechanic

y= hourly rate of the second mechanic

Derive two equations to solve for the two unknowns

10x + 15y = 1900 (1)

x + y = 155 (2)

From (2)

x + y = 155

x=155-y

Substitute x=155-y into (1)

10x + 15y = 1900

10(155-y) + 15y =1900

1550 -10y + 15y =1900

5y =1900-1550

5y=350

Divide both sides by 5

y= 70

Substitute y=70 into (2)

x + y = 155

x + (70) =155

x=155 - 70

= 85

x= 85

The rate charged by first mechanic per hour= x =$85

The rat charged by second mechanic per hour =y = $70

In Parallelogram DEFG, DH= x+3, HF= 3y, GH= 2x-5, and HE= 5y+2. Find the values of x and y.

Answers

Answer:

y=13  , x=36

Step-by-step explanation:

The diagonal of parallelogram bisect at a point where the sides across the intersection are equal

DH=HF

x+3=3y

x=3y-3   first equation

HE=GH

2x-5=5y+2 ⇒ 2x-5y=7 second equation

solve by substitution: x=3y-3

2x-5y=7

2(3y-3)-5y=7

6y-6-5y=7

y=7+6

y=13

x=3y-3

x=3(13)-3

x=36

Hannah’s mom bought a variety pack of chips. There were a total of 12 bags. Her mom put the bags in a jar. There were 5 barbecue,3 plain,3 sour cream, and 1 tortilla.

What is the probability of Hannah selecting a bag of barbecue chips if she doesn’t look in the jar?

A.) 5/12
B.) 5/7
C.) 12/5
D.) 1/12
E.) 7/12

Answers

Answer:

5/12

Step-by-step explanation:

There is a total of 12 bags,  5 of which are bbq

P ( bbq) = number of bbq/ total

             = 5/12

A toy box in the shape of a rectangular prism has a volume of 6,912 cubic inches. The base area of the toy box is 288 square inches. What is the height of the toy box?

Answers

Answer:

h= 24 inches

Step-by-step explanation:

(Volume)= (Base Area) * (Height)

6,912= 288h

h=

F(x)=0.5x^2-2 and g(x)=8x^3+2

Answers

Answer:

(f*g)(x) = 4x⁵ - 16x³ + x² - 4

Step-by-step explanation:

To find (f*g)(x), you need to multiply f(x) with g(x).  Use FOIL to multiply.

f(x) = 0.5x² - 2

g(x) = 8x³ + 2

(f*g)(x) = (0.5x² - 2)(8x³ + 2)

(f*g)(x) = 4x⁵ + x² - 16x³ - 4

(f*g)(x) = 4x⁵ - 16x³ + x² - 4

Null hypothesis: There is no difference in the average start-up costs of the 4 different types of shops. Alternative hypothesis: There is a difference in the average start-up costs of the shops

Answers

Answer:

True

Step-by-step explanation:

The null and alternate hypothesis are established terms that are used in statistics. Note that the Null hypothesis often represents the expected outcome, as in this example that– "There is no difference in the average start-up costs of the 4 different types of shops".

Meanwhile, the Alternative hypothesis tells the opposite of expected outcome– "There is a difference in the average start-up costs of the shops working statement".

Thus, the forcus of the research would be to prove whether the null hypothesis is true or false. If it is true, then we fail to reject the null hypothesis.

Use the substitution method to solve the system of equations. Choose the correct ordered pair.

Answers

Answer:

b

Step-by-step explanation:

Answer:

The answer is D or (10,-9)

Step-by-step explanation:

Since y is already given (and you have to use the substitution method) substitute y into one of the equations. So you should have something like this:

-2x+11=3x+21

After that merely solve for x which should get you x=10. After you get your x value plug 10 in either (of the original) equation and your y value should be -9. For example if you chose y=-2x+11 you should have y= -2(10)+11. In the end your answer should be (10,-9).

If you want to check your work merely plug your answer into both equations (ex: -9=-2(10)+11 --> -9=-9), therefore you know your answer is correct).

Hope this helped!

what is the value of digit 9 in 3.45×0.27×0.3 ? ​

Answers

Answer:

[tex]\boxed{\pink{0.27945}}[/tex]

Step-by-step explanation:

[tex]3.45 \times 0.27 \\ = 0.9315 \times 0.3 \\ = 0.27945[/tex]

Answer: thousandths place

Step-by-step explanation:

                                      ↓

3.45 x 0.27 x 0.3 = 0.27945

                                     

The place values to the right of the decimal point are:

one to the right (2): tenths

two to the right (7): hundredths

three to the right (9): thousandths

four to the right (4): ten thousandths

five to the right (5): hundred thousandths

another one another one...........

Answers

Answer:

B

Hope it helped you out

Tysm

Which statement about this figure is true ?

a. it has reflection al symmetry with one line of symmetry

b. it has no rotational symmetry

c. it has no rotational symmetry with an angle of rotation of 90 degrees

d. it has no reflectional symmetry

Answers

Its B because if you were to rotate the bottom to left or right it wouldnt be symmetrical

The statement that is true about the given figure, a limaçon, is c. It has no rotational symmetry, with an angle of rotation of 90 degrees.

Let's examine each option and explain why they are true or false:

a. It has reflectional symmetry with one line of symmetry: This option is false. To have reflectional symmetry with one line of symmetry, the figure must be identical on both sides when divided by a line. The given figure, a limaçon, does not exhibit this property.

b. It has no rotational symmetry: This option is true. Rotational symmetry means that the figure remains unchanged after rotation by certain angles. The limaçon does not have any rotational symmetry because it does not appear the same after any rotation.

c. It has no rotational symmetry, with an angle of rotation of 90 degrees: This option is true. A figure with rotational symmetry of 90 degrees would appear the same after a 90-degree rotation. However, the limacon does not exhibit this property.

d. It has no reflectional symmetry: This option is true. Reflectional symmetry requires the figure to have a line of symmetry dividing it into two identical halves. The limaçon does not possess such a line of symmetry.

Based on the explanations above, the correct statement is that the limaçon has no rotational symmetry with an angle of rotation of 90 degrees (option c).

Learn more about symmetry here:

https://brainly.com/question/32342060

#SPJ4

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