solve for x.
a. 2
b. 5
c. 0
d. 7

Answer:

[tex]55[/tex]

Step-by-step explanation:

We'll be using case-work to solve this problem. Let's call the ones digit of the telephone number [tex]B[/tex] and the tens digit [tex]A[/tex]. Each telephone number can be represented as [tex]AB[/tex].

Since the question states that numbers that are smaller when their digits are reversed are not used, we have the following inequality:

[tex]B\geq A[/tex]

This is because if [tex]A>B[/tex], the number would become smaller when [tex]A[/tex] and [tex]B[/tex] are switched in [tex]AB[/tex]. However, if [tex]A=B[/tex] or [tex]B>A[/tex], the number will not become smaller.

Let's work our way up starting with [tex]A=0[/tex]. If [tex]A=0[/tex], there are 10 other numbers (0-9) that we can choose for [tex]B[/tex] that adhere to the condition [tex]B\geq A[/tex]:

[tex]0B,\\01, 02, 03,...[/tex]

Therefore, there are 10 possible telephone numbers when the tens digit is 0.

Repeat the process, now assigning [tex]A=1[/tex]. Now, we only have the digits 1-9 to choose from for [tex]B[/tex], since [tex]B[/tex] needs to be greater than or equal to A. Therefore, there are 9 possible telephone numbers when the tens digit is 1.

This pattern continues. As we work our way up through the cases (when increasing [tex]A[/tex] by 1), the number of possible telephone numbers decreases by 1, since there becomes one less option for [tex]B[/tex].

The last case would be [tex]A=9[/tex] in which case there would only be one option for [tex]B[/tex] and that would be 9.

Since there are 10 cases (0-9), add up the possible telephone numbers for each case:

[tex]\displaystyle \sum_{n=1}^{10}n=1+2+3+4+5+6+7+8+9+10=\boxed{55}[/tex]

Alternatively, recall that the sum of this series can be found using [tex]\frac{n(n+1)}{2}[/tex], where [tex]n[/tex] is the number of values in the set. In this case, [tex]n=10[/tex], and we have:

[tex]1+2+3+4+5+6+7+8+9+10=\frac{10(11)}{2}=\frac{110}{2}=\boxed{55}[/tex]

●✴︎✴︎✴︎✴︎✴︎✴︎✴︎✴︎❀✴︎✴︎✴︎✴︎✴︎✴︎✴︎✴︎✴︎●

Hi my lil bunny!

❧⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯☙

If an octagon is 24, how many is a pentagon?

Ans : Pentagon has 5 sides.

( A five-sided shape is called a pentagon. A six-sided shape is a hexagon, a seven-sided shape a heptagon, while an octagon has eight sides. The names of polygons are derived from the prefixes of ancient Greek numbers. )

❧⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯☙

●✴︎✴︎✴︎✴︎✴︎✴︎✴︎✴︎❀✴︎✴︎✴︎✴︎✴︎✴︎✴︎✴︎✴︎●

Have a great day/night!

❀*May*❀

The pentagon is 15, when octagon is 24.

What is Polygon?

A polygon is a figure made up of line segments (not curves) in a two-dimensional plane. Polygon is the combination of two words, i.e. poly (means many) and gon (means sides).

Polygon with 8 sides known as Octagon and polygon with 5 sides known as Pentagon.

Here, given that, Octagon = 8 sides = 24

So, 1 side= 3

Then, we get, pentagon = 5 sides = (5×3) = 15

Hence, the pentagon is 15.

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Answer:

23.4458015822

Step-by-step explanation:

tan(21) = 9/x

9/tan(21) = x

9/tan(21) = 23.4458015822

Answer:

The answer is A - Radicand.

Hope that helps!

Answer:

(6) the letter n : intersection which means the number you will find at the first bracket and has the same number at the other bracket

Answer:

(x + 2 x) * t = 300 km

3x = 300 km/ 2 hrs = 150 km / hr

x = 50 km / hr

One car traveled at 50 km / hr and the other at 100 km / hr

In 2 hours they traveled 300 km

The speed of the first car is 100 km/hr and that of the second car is 50 km/hr.

Work is the completion of any task for example if you have done your homework in 5 hours then you have done 5 hours.

Another illustration of labor is when you finish your meal in an hour, which means that you finished your work in an hour. In essence, work is the length of time it took you to complete any task.

Speed of the second car is = v

The speed of the first car = 2v

Given that

Distance covered by = 300 km

Time taken = 2 hr

By relative velocity concept

2v + v = 300/2

3v = 150

v = 50 km/hr.

Hence the speed of the first car will be 100 km/hr and that of the second car will be 50 km/hr.

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Answer:

Height= 4.5 Volume= 91.125

Step-by-step explanation:

Answer:

The answer is about 15 cm because if you use a ruler, it is a little under 15cm

Step-by-step explanation:

Answer:

15cm

Step-by-step explanation:

most pens are under 15 cm by a a couple of millimeters. 15 cm  is in fact the best estimate. It really depends on the pen your using but the average pen is about 15 cm.

Answer:

Step-by-step explanation:

[tex]\sqrt{x-3} +5=x\\\sqrt{x-3} =x-5\\squaring ~both~sides\\x-3=x^2-10x+25\\x^2-10x-x+25+3=0\\x^2-11x+28=0\\x^2-7x-4x+28=0\\x(x-7)-4(x-7)=0\\(x-7)(x-4)=0\\x=7,4[/tex]

put x=7 in the given equation

[tex]\sqrt{7-3} +5=7\\\sqrt{4} +5=7\\2+5=7\\7=7[/tex]

which is true .

∴ x=7 is a solution of the given eq.

now put x=4 in the given eq.

[tex]\sqrt{4-3} +5=7\\1+5=7\\6=7\\[/tex]

which is not true.

∴x=4 is an extraneous solution.

Answer:

5

Step-by-step explanation:

Answer:

5 is the answer to the question.

Step-by-step explanation:

(3² - 8) + 4

= (3×3×3 - 8) + 4

= (9 - 8) + 4

= 1 - 4

= 5

Step-by-step explanation:

phukan = x

Nanwan = y

let this be a simultaneous equation.

x - y = 18.... equation i

x + y = 100.... equation ii

subtract equation i from equation ii

= 2y = 118

y = 59

substitute y = 59 in equation ii to get x

x + 59 = 100

x = 100- 59

x = 41

Nanwan = 59, Phukan = 41

Answer:

Nawman = 59 years

Phukan = 41 years

Step-by-step explanation:

P = N - 18

P + N = 100

(N - 18) + N = 100

2N = 100 + 18

2N = 118

N = 118 : 2

N = 59 years

P = (59 - 18) years

P = 41 years

Answer:

Ông sáu sẽ mất 4281000 đồng

Answer:

750

300

390, 570

120,750

2.28

15.87

Step-by-step explanation:

Answer:

12

Step-by-step explanation:

since the function is -2x+8 and you have been told to find f(-1.8) you have to replace -1.8 were there's x in the function.

f(x)=-2x+8

f(-1.8)=-2x+8

=-2(-1.8)+8

=3.6+8

=11.6 round off to 12

I hope this helps

Answer:

10

Step-by-step explanation:

Don't look at the other persons' answer, its wrong. The answer is 10 because I retook the quiz 3 TIMES until I got the right answer because the other people couldn't provide the right answer. All in all, I wish you all luck on your quiz and I hope you get it right! <3

Answer:

Equation A is true; Equation B is not

Step-by-step explanation:

There is a standard formula for the "difference of cubes" that is:

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

and this perfectly matches equation A.

Equation B has the square of n (n^2) on the left side but not on the right side.  Thus this is not an identity.

Answer:

The area of the circle is exactly π times the square of its radius. If you are given that the radius is within 0.1cm of 8.5cm, i.e. lies between 8.4 cm and 8.6 cm, its square will lie between p=8.4² = 70.56 and q=8.6² = 73.96 cm².

Answer:

The area of the circle is exactly π times the square of its radius. If you are given that the radius is within 0.1cm of 8.5cm, i.e. lies between 8.4 cm and 8.6 cm, its square will lie between p=8.4² = 70.56 and q=8.6² = 73.96 cm².

Step-by-step explanation:

thanks for question dear

Answer:

57 shirts were left over

Step-by-step explanation:

57 multiplied by 80 gives you 4480

4537 subtracted by 4480 gives you 57 leaving you with 57 shirts left over :)

Answer:

That Ratios aren't equal.

Step-by-step explanation:

Given: DE is || to BC.

So in order to make this false then we have to say that the sides aren't proprtional, making it not possible to get the ratios equal.

(See the Triangle proprtionality theorem or the triangle midsegment theorem)      

Answer:

4:10 ≠ 6:14

Step-by-step explanation:

bc i said so

Answer:

Hope this helps you.

Step-by-step explanation:

I plugged in x for t, but it is the same graph.

Answer:

  rational, integer, whole, natural, real

Step-by-step explanation:

Trailing zeros after the decimal point do not change the value of a number. This number is 1, a rational, real, integer, whole, natural number.

Everything you answered so far looks good. Nice work.

For question 10, we need to find two numbers that multiply to 3(-1) = -3 and also add to 2. The 3 and -1 are the first coefficient and last term. The 2 is the middle coefficient.

Through trial and error, the two numbers we're after are 3 and -1

3 times -1 = -3

3 plus -1 = 2

We break up the 2x into 3x - 1x and factor like so...

3x^2 + 2x - 1

3x^2 + 3x - 1x - 1 ... replace 2x with 3x-1x

(3x^2+3x) + (-1x-1) ... pair up terms

3x(x+1) - 1(x+1) .... factor each parenthesis group

(3x-1)(x+1) ... pull out the gcf (x+1)

You can use FOIL, the box method, or distribution to go from (3x-1)(x+1) back to 3x^2+2x-1 again.

Answer:

Step-by-step explanation:

Answer:

Step-by-step explanation:

Hello, please consider the following.

[tex]h(x)=5/2x+4 \\\\x=(h^{-1}o})(x)=(hoh^{-1})(x)=h(h^{-1}(x))=\dfrac{5}{2h^{-1}(x)+4}\\\\<=> 2h^{-1}(x)+4=\dfrac{5}{x}\\\\<=> h^{-1}=\dfrac{\dfrac{5}{x}-4}{2}\\\\<=>h^{-1}=\dfrac{5-4x}{2x}[/tex]

Thank you.

Answer:

1. 30:100 = 30/100=3/10

2. 2:8, 3:12

3. 60:12 = 5:1 or 5/1

Step-by-step explanation:

The given statement is false as taking a survey on the heights of all your classmates is an example of quantitative data.

Quantitative data is data that can be measured and expressed as numbers,

such as height, weight, age, etc. Categorical data, on the other hand, consists of distinct categories or groups, such as eye color, gender, favorite color, etc.

Data can be classified into two main types: quantitative data and categorical data.

Quantitative data:

Quantitative data is numerical data that represents measurements or quantities.

It deals with things that can be measured and expressed as numbers.

For example, the heights of people, the weights of objects, the ages of individuals, and the temperatures in degrees are all examples of quantitative data.

Quantitative data can be further divided into two subtypes: discrete and continuous data.

Discrete data: Discrete data consists of whole numbers that cannot be further divided into smaller parts.

For example, the number of students in a class, the number of cars in a parking lot, and the number of books on a shelf are all examples of discrete data.

Continuous data: Continuous data consists of real numbers that can take on any value within a specific range.

For example, the height of a person can be measured as 165.5 cm, 170.2 cm, 178.9 cm, etc. These are all examples of continuous data.

Categorical data:

Categorical data, also known as qualitative data, involves the grouping of items into categories or classes.

It represents characteristics or attributes and is not numerical in nature. Categorical data is further divided into two subtypes: nominal and ordinal data.

Nominal data: Nominal data consists of categories with no intrinsic order or ranking.

For example, eye color ( blue, brown, green) and types of fruits (e.g., apple, banana, orange) are examples of nominal data.

Ordinal data: Ordinal data consists of categories with a meaningful order or ranking.

However, the differences between the categories are not quantifiable.

For instance, educational levels (elementary, middle, high school) and satisfaction levels (very satisfied, satisfied, neutral, dissatisfied, very dissatisfied) are examples of ordinal data.

The height survey of classmates, the data collected would be numerical values representing the heights of each individual.

Since heights are measured and expressed as numbers, this falls under quantitative data, not categorical data.

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Answer:

A=d-c/b

Step-by-step explanation:

Answer:

ab+c=d

Step-by-step explanation:

just took the test

Answer:

Pregunta 1: Opcion D. 8

Pregunta 2: Opción A. 19 (aunque lo correcto es decir que son 20)

Pregunta 3: 28 años (no está como opción)

Pregunta 4: Opción D. 1/3

Step-by-step explanation:

Las fracciones irreductibles son aquellas que después de dividirlas por un común divisor, una vez que no se pueden dividir más se dice que son irreducibles, por lo tanto no existe ningún número que sea divisor común del numerador y del denominador más que 1.

Fracciones irreductibles con común denominador 24.

Como máximo divisor tenemos el 24 y como mínimo el 1

entre 1/24 y 1 estarán nuestras fracciones o sea:

1/24 < x/24 < 1. Ahora convertimos el 1 en fracción de 24, lo que sería 24/24 para igualar el numerador en ambos lados de la ecuación, para poder determinar x

1/24 < x/24 < 24/24

Como vemos que x tiene que estar entre 1 y 24, las respuestas serán:

2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22 y 23

Eliminamos los números divisores de 24, aquellos pares, y nos focalizamos en los que no podriamos dividir por nada con 24, o sea los números primos

5, 7, 11, 13, 17, 19, 23. Como nos falta el 1, obtenemos un total de 8 fracciones: 1/24, 5/24, 7/24, 11/24, 13/24, 17/24, 19/24, 23/24

Mismo procedimiento para el 25:

1/25 es una de las fracciones irreductibles. Pensamos en los valores de x

1/25 < x/25 < 25/25

2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25

Los números divisibles por 25, son los multiplos de 5, asi que esas respuestas no irían. Las fracciones irreductibles son:

1/25, 2/25, 3/25, 4/25, 6/25, 7/25, 8/25, 9/25, 11/25, 12/25, 13/25, 14/25, 16/25, 17/25, 18/25, 19/25, 21/25, 22/25, 23/25 y 24/25 haciendo un total de

20. Por alguna razón está mal formulada la pregunta, son 20 pero no está como opción y como te piden fraccion impropia (numerador > denominador), contamos a partir de 26. FIjate que hasta el proximo entero que sería 50/25, también son 20 fracciones (irreductibles e impropias)

26/25, 27/25, 28/25, 29/25, 31/25, 32/25, 33/25, 34/25, 36/25, 37/25, 38/25, 39/25, 41/25, 42/25, 43/25, 44/25, 46/25, 47/25, 48/25, 49/25

Próxima pregunta:

Miguel tiene 4/5 de la edad de la novia, y ambas edades suman 63.

Plantiemos la siguiente ecuacion donde x es la edad de la novia

4/5x + x = 63

9/5x = 63

x = 63 . 5/9 (como 9/5 pasa al otro lado de la igualdad dividiendo, damos vuelta la fraccion multiplicandola)

x = 35

Si la novia tiene 35 años y la edad de Miguel es 4/5 de esa edad

4/5 .35 = (35 .4) /5 = 28

Es raro porque no está la respuesta como tal.

Próxima pregunta:

Al ser las 8 am, quiere decir que han pasado 8 horas de que empezó el día

y el día tiene 24 horas.

8 horas transcurridas / 24 horas totales = 1/3

Answer:

always true because the negative value of y is cancelld by - sign so it becomes x+|y|

examples: x=1, y=-1 then 1-(-1)>0

x=2, y=-5 then 2-(-5)>0

Answer: D

Step-by-step explanation:

3/4 is equal to 0.75.

A is pretty easy. You just add the numerator and get 3/4. So, that is NOT the answer.

B is 9/12. If you divide 9 and 12, it gives 0.75, which is equal to 0.75. This NOT the answer.

C is 6/8 and simplifies into 3/4 so is this is NOT the answer.

D is 3/12 and when you dividere the umerator and the denominator, it gives 0.25 or 1/4, which isn’t equal to 3/4. This IS the answer.

Hope this helped!

The expression that is not equal to 3/4 will be 1/12 + 2/12. Then the correct option is D.

Algebra is the study of abstract symbols, while logic is the manipulation of all those ideas.

The acronym PEMDAS stands for Parenthesis, Exponent, Multiplication, Division, Addition, and Subtraction. This approach is used to answer the problem correctly and completely.

Let's check all the options. Then we have

A. 1/4 + 1/4 + 1/4, then the value of the expression is given as,

1/4 + 1/4 + 1/4 = 3/4

B. 1/8 + 1/8 + 1/8 + 1/8 + 1/8 + 1/8, then the value of the expression is given as,

1/8 + 1/8 + 1/8 + 1/8 + 1/8 + 1/8 = 6 / 8

1/8 + 1/8 + 1/8 + 1/8 + 1/8 + 1/8 = 3 / 4

C. 3 / 12 + 6 / 12, then the value of the expression is given as,

3 / 12 + 6 / 12 = 9 / 12

3 / 12 + 6 / 12 = 3 / 4

D. 1 / 12 + 2 / 12, then the value of the expression is given as,

1/12 + 2/12 = 3 / 12

1/12 + 2/12 = 1 / 4

The expression that is not equal to 3/4 will be 1/12 + 2/12. Then the correct option is D.

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Answer:

Step-by-step explanation:

 [tex]\left(\frac12x+\frac12y\right)^2=\\\\=\left[\frac12(x+y)\right]^2=\\\\=\left(\frac12\right)^2\left(x+y\right)^2=\\\\=\frac14\left(x+y\right)^2=\\\\=\frac14(x^2+2xy+y^2)=\\\\=\frac14(x^2+y^2+2xy)=\\\\=\frac14(14+2\cdot5)=\\\\=\frac14\cdot28=\\\\=7[/tex]