From a group of three boys and six girls a boy and a girl will be selected to attend a conference and how many ways can the selection you made

1.) 10+2√21

2.) 8-2√15

3.) 38+2√10

solution to all the answers:

NUMBER 1:

=> use (a + b)^2 + 2ab + b^2 to expand the expression (√3 +√7)^2, then it should look like this: 3 + 2√21 + 7.

=> add the numbers: 10 + 2√21.

NUMBER 2:

=> use (a + b)^2 + 2ab + b^2 to expand the expression (√5 -√3)^2, then it should look like this: 5 - 2√15 + 3.

=> add the numbers: 8 - 2√15.

NUMBER 3:

=> use (a + b)^2 + 2ab + b^2 to expand the expression (2√5 + 3√2)^2, then it should look like this: 20 + 12√10 + 18.

=> add the numbers: 38 + 12√10.

I HOPE THIS HELPED!!

Answer:

12

Step-by-step explanation:

AC = BD (as the diagonal of the rectangle)

4x-60=30-x

4x+x = 30+60

5x = 90

x = 90/5

x = 18

=> BD = 30-18 = 12

Answer:

Step-by-step explanation:

I can't get the exact answer you've given, but I can tell you some things about it. The largest number in the denominator is 30 or 31. That's because 31 * 3 is 93 exactly. However the fraction is a problem and will likely push you over 100.

3.675 * 31 = 113 something. So 31 is too big.

The closes I came was 98 / 26 which is 3.769

Answer:

1) B, 48

2) C. 180=2x2x3x15

Step-by-step explanation:

To find the missing value divide both sides by -7:

28/-7 = 4

The missing value is 4

Answer= -4

Step-by-step explanation:

negative × negative = positve. therefore if 7×4=28 , then -7×-4=28

Answer:

[tex]\frac{x+4}{4x-4}[/tex]

Step-by-step explanation:

Answer:

45.1

Step-by-step explanation:

m<A = 51°

For angle A, BC is the opposite leg.

AB is the hypotenuse.

sin A = opp/hyp

sin 51° = BC/58

BC = 58 * sin 51°

BC = 45.1

Answer:

the previous population was 62,000.

Step-by-step explanation:

The current population of a city = 83,700

The population of a city has increased by 35% since it was last measured.

We have to calculate the previous population before increasing 35%.

Let the previous population be p

p +(35% × p) = 83,700

p + 0.35p = 83,700

1.35p = 83,700

p =  

p = 62,000

Therefore, the previous population was 62,000.

The population of a city has increased by 27% since it was last measured and the previous population was 62,000.

The current population of a city = 83,700

The population of a city has increased by 35% since it was last measured.

We have to calculate the previous population before increasing 35%.

A population is a distinct group of individuals, whether that group comprises a nation or a group of people with a common characteristic.

Let the previous population be p

p +(35% × p) = 83,700

p + 0.35p = 83,700

p = 83,700

p =  [tex]\frac{ 83,700}{1.35}[/tex]

p = 62,000

Therefore, the previous population was 62,000.

To learn more about the population visit:

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Answer:

The answer is "[tex]\frac{1}{2}[/tex]".

Step-by-step explanation:

Given points:

[tex](-2,3)\\\\(2,5)\\\\[/tex]

average rate=?

[tex]x_1=-2\\\\y_1=3\\\\x_2=2\\\\y_2=5[/tex]

[tex]average\ rate=\frac{y_2-y_1}{x_2-x_1}[/tex]

                     [tex]=\frac{5-3}{2-(-2)}\\\\=\frac{5-3}{2+2}\\\\=\frac{2}{4}\\\\=\frac{1}{2}[/tex]

Answer:

2m² + 14m + 2

Step-by-step explanation:

3A + B

= 3(2m + 1) + 2m² - 1 + 8m ← distribute parenthesis by 3

= 6m + 3 + 2m² - 1 + 8m ← collect like terms

= 2m² + 14m + 2 ← in standard form

Answer:

The answer is 97!

Step-by-step explanation:

The formula for Pythagorean Theorem is a^2+b^2=c^2. (65)^2 + (72)^2 is 9409, which has a square root of 97. Hope this helped! :)

Answer:

1.5 yrs

Step-by-step explanation:

let the present age=x

x+5=2+3x

3x-x=5-2

2x=3

x=3/2=1.5 years

Answer:

3x + 2 = x + 5.

Step-by-step explanation:

Peter is currently x years old. In 5 years, his age will be x + 5. According to the prompt, Peter's age will be 2 + 3 times his current age, x, which can be represented as 2 + 3x. 2 + 3x is the same age as x + 5, so we can represent it as...

2 + 3x = x + 5

3x - x = 5 - 2

2x = 3

x = 1.5

This means that Peter is 1.5 years old.

Hope this helps!

Answer:

57.2

Step-by-step explanation:

This is a right triangle so we can use trig ratios.

We are asked to find a side when we know a angle adjacent to that side. And we are given a side opposite of that angle. We can use Tangent to find the side length.

[tex] \tan(40) = \frac{48}{x} [/tex]

Take the reciprocal of both sides.

[tex] \frac{1}{ \tan( 40) ) } = \frac{x}{ 48} [/tex]

Multiply both sides by 48.

[tex] x = \frac{1}{ \tan(40) } \times 48[/tex]

[tex]x = 57.2[/tex]

Answer:

No solution

Step-by-step explanation:

A solution for a system of equations entails that all variables are the same. In this case, it means that both x and y must be the same.

Looking at the graph, there is no spot where y=3x+3 and 3x-y=2 intersect

To confirm, we can look at the equations. If we make them both equal to y, we can set them equal to each other.

For y=3x+3, this is already set to y. For 3x-y=2, we can add y to both sides and subtract 2 from both sides to get

3x-2=y

3x+3=y

Since the x and y values must be the same, we can say that

3x-2=3x+3

subtract 3x from both sides

-2 = 3

Since -2 is not equal to 3, we can confirm that there are no solutions to this system of equations

Answer:

D

Step-by-step explanation:

This isnt a cartisean coordinate plane so A is wrong. One of our points is at

[tex] - 3 + i[/tex]

Because it coincide with real number 3, and negative imaginary number i.

Conjugates are terms with opposite inverse of terms.

So our conjugates is

[tex] - 3 - i[/tex]

Answer: 20 boxes

Step-by-step explanation:

First and foremost, we need to know that 1 foot = 12 inches. Therefore, 1500 feet will be converted to inches and this will be:

1500 feet = 1500 × 12 = 18000 inches

Since each group of box requires 900 inches, then the number of group of boxes that can be used in this case will be:

= 18000/900.

= 20 groups of boxes

Answer:

Answer of this qn is 96cm^2

Answer:

A.

Step-by-step explanation:

42,000 units

Answer:

D.

Step-by-step explanation:

The line will be a straight line and will go through AB in the center. Therefore, it will be the perpendicular bisector.

Answer:

Step-by-step explanation:

Let

x = cost per mile

y = Total cost

Plan 1:

y = 59 + 0.15x

Plan 2:

y = 50 + 0.20x

Equate the total cost of the two plans

59 + 0.15x = 50 + 0.20x

59 - 50 = 0.20x - 0.15x

9 = 0.05x

x = 9/0.05

= 180

x = 180 miles

y = 50 + 0.20x

= 50 + 0.20(180)

= 50 + 36

= 86

y = 86

Answer:

j = 10.1

Step-by-step explanation:

The difference between 9.5 and 11.3 is

11.3 - 9.5 = 1.8

This is split into 3 divisions, that is

1.8 ÷ 3 = 0.6

Then

j = 9.5 + 0.6 = 10.1

Answer:

C

Step-by-step explanation:

[tex] \frac{x}{3} [/tex]

Answer:

a round plane figure whose boundary (the circumference) consists of points equidistant from a fixed point (the center)

Explanation:

Oxford dictionary definition

Step-by-step explanation:

a circle is a shape consisting of all points in a plane that are at a given distance from a given point the center

Step-by-step explanation:

hey can I have this question in English write can totally ask your question I don't think that I am doing this for purposes please ask this question and English so I can ask this question please ask this question in English if you I am from India so I don't know this all languages Thank you

Answer:

10% of 55

=> 10/100 × 55

=> 1/10×55

=> 5.5

55 increased by 10% => 55 + 5.5

=> 60.5

hope that helps ✌

Answer:

Step-by-step explanation:

10% of 55

10/100*55

1/10*55

5.5 <--- That is 10% of 55

55+5.5 = 60.5

9514 1404 393

Answer:

  see attached

Step-by-step explanation:

The usual glide slope for landing is about 3°. The descent rate here of 0.25 km/min corresponds to 15 km/h. For the slope to be 3°, the forward speed of the airplane would need to be 286 km/h, about 154 knots.

This is not unreasonable for an approach speed for a (very) heavy airplane. Usually, the rate would be a little lower, but we wanted something that would fit on the grid provided.

Answer:

[tex]81\frac{2}{3}[/tex] hours

Step-by-step explanation:

Hi there!

1) Create a proportion

[tex]\frac{7h}{120mi}=\frac{x}{1400 mi}[/tex]

[tex]\frac{7}{120}=\frac{x}{1400}[/tex]

2) Solve for x

[tex]\frac{7}{120}=\frac{x}{1400}[/tex]

Multiply both sides by 1400

[tex]\frac{7}{120}*1400=\frac{x}{1400}*1400[/tex]

[tex]\frac{245}{3} =x[/tex]

[tex]\frac{245}{3} =x[/tex]

[tex]81\frac{2}{3} =x[/tex]

Therefore, it would take the van [tex]81\frac{2}{3}[/tex] hours to travel 1400 miles at the same speed.

I hope this helps!

Answer: x=2

Step-by-step explanation:

[tex]2x(9x-4)-3x(6x-7)=26\\18x-8x-18x+21x=26\\10x-18x+21x=26\\-8x+21x=26\\13x=26\\x=2[/tex]

Answer:

top to bottom, the answers are b, c, a

Step-by-step explanation:

One way to find the solution to a system of equations is to substitute values in. For the first one,

y=2x+3

y=2x+5,

we can substitute 2x+3 =y into the second equation to get

y=2x+5

2x+3 = 2x+5

subtract 2x from both sides

3 = 5

As 3 is not equal to 5, this is never equal and therefore has no solution

For the second one,

y= 2x+7

y = (-2/3)x + 10

We can plug y=2x+7 into the second equation to get

2x + 7 = y = (-2/3)x + 10

2x + 7 = (-2/3)x + 10

add (2/3)x to both sides to make all x values on one side

2x + (2/3)x + 7  = 10

subtract 7 from both sides to make only x values on one side and only constants on the other

2x + (2/3)x = 3

(6/3)x + (2/3)x = 3

(8/3)x = 3

multiply both sides by 3 to remove a denominator

8x = 9

divide both sides by 8 to isolate x

x=9/8

There is only one value for when the equations are equal, so this has one solution

For the third one

y = x-5

2y = 2x - 10

Plug x-5 = y into the second equation

2 * y= 2*(x-5)

2 * (x-5) = 2x - 10

2x-10 = 2x-10

add 10 to both sides

2x=2x

As 2x is always equal to 2x, no matter what x is, there are infinitely many solutions for this system

Answer: (3b+2)(b+2)

Step-by-step explanation: