There are 45 pupils in a competition. 2/5 of the pupils are girls. How many boys are there in the competition?

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Explanation:

It helps to add point labels. Let's place point A at the very top point of the triangle. Then point B will be at the 90 degree angle. Point C is the far left point. Lastly, point D is on segment BC such that DC = 3.

Since BC = 8 and CA = 17, we can use the pythagorean theorem to get...

(AB)^2 + (BC)^2 = (AC)^2

(AB)^2 + (8)^2 = (17)^2

(AB)^2 + 64 = 289

(AB)^2 = 289-64

(AB)^2 = 225

AB = sqrt(225)

AB = 15

Now focus on triangle ABD and apply the pythagorean theorem again to find side AD

(AB)^2 + (BD)^2 = (AD)^2

AD = sqrt(  (AB)^2 + (BD)^2  )

AD = sqrt(  (AB)^2 + (BC-CD)^2  )

AD = sqrt( (15)^2 + (8-3)^2 )

AD = sqrt(250)

AD = sqrt(25*10)

AD = sqrt(25)*sqrt(10)

AD = 5*sqrt(10) .... answer is choice B

Answer:

The speed is 20.8  m/s

Step-by-step explanation:

If a projectile ascends vertically, and after 3 seconds it reaches its maximum height, calculate the velocity that it carries to the middle of its downward trajectory

Let the maximum height is h and initial velocity is u.

From first equation of motion

v = u + at

0 = u - g x 3

u = 3 g.....(1)

Use third equation of motion

[tex]v^2 = u^2 - 2 gh \\\\0 = 9 g^2 - 2 gh \\\\h = 4.5 g[/tex]

Let the speed at half the height is v'.

[tex]v^2 = u^2 + 2 gh \\\\v'^2 = 0 + 2 g\times 2.25 g\\\\v'^2 = 4.5\times 9.8\times9.8\\\\v' = 20.8 m/s[/tex]

Answer:

1 7/12 acres of land

Step-by-step explanation:

Tomatoes = 1/3 acre of land

Corn = 3/4 acre of land

Carrots = 1/2 acre of land

Total acres of land he planted = tomatoes + corn + carrots

= 1/3 + 3/4 + 1/2

= (4+9+6) / 12

= 19/12 acres

= 1 7/12 acres of land

Or

= 1.5833333333333 acres

Total acres of land he planted = 1 7/12 acres of land

None of the given options is correct

Answer:

The slope is -3/4 and a point on the line is (-5,4)

Step-by-step explanation:

This equation is in point slope form

y -y1 = m(x-x1)

where m is the slope and (x1,y1) is a point on the line

Y-4=-3/4(x+5)

Y-4=-3/4(x -  -5)

The slope is -3/4 and a point on the line is (-5,4)

Answer:

9

Step-by-step explanation:

Using the rules of logarithms

log[tex]x^{n}[/tex] = nlogx

[tex]log_{b}[/tex] b = 1

Then

[tex]log_{x}[/tex] [tex]x^{9}[/tex]

= 9[tex]log_{x}[/tex] x

= 9

Answer:

18

Step-by-step explanation:

The interior and exterior angle of a polygon is supplementary

let interior be I

let exterior be E

I + E = 180

Since the interior angle is 8 times that of an exterior angle,

8E + E = 180          [replacing I with 8E]  

9E = 180                

E = 20                      

The exterior angle is 20 degrees

I + E = 180          

I + 20 = 180      

I = 160              

The interior angle is 160 degrees.

The equation to find the interior angle of a polygon with 'n' number of sides is:

I = ( (n − 2) × 180 ) ⁄ n

We know the interior angle, so plug it in and solve for n:

160 = ( (n − 2) × 180 ) ⁄ n      

160n = (n − 2) × 180            

160n = 180n − 360                  

-20n = -360                            

n = 18                                  

Answer:

Question 16 = 22

Question 17 = 20 cm²

Step-by-step explanation:

Concepts:

Area of Square = s²

Area of Triangle = bh/2

Diagonals of the square are congruent and bisect each other, which forms a right angle with 90°

Segment addition postulate states that given 2 points A and C, a third point B lies on the line segment AC if and only if the distances between the points satisfy the equation AB + BC = AC.

Solve:

Question # 16

Step One: Find the total area of two squares

Large square: 5 × 5 = 25

Small square: 2 × 2 = 4

25 + 4 = 29

Step Two: Find the area of the blank triangle

b = 5 + 2 = 7

h = 2

A = bh / 2

A = (7) (2) / 2

A = 14 / 2

A = 7

Step Three: Subtract the area of the blank triangle from the total area

Total area = 29

Area of Square = 7

29 - 7 = 22

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Question # 17

Step One: Find the length of PT

Given:

PT = PR + RT [Segment addition postulate]

PT = (4) + (6)

PT = 10 cm

Step Two: Find the length of S to PT perpendicularly

According to the diagonal are perpendicular to each other and congruent. Therefore, the length of S to PT perpendicularly is half of the diagonal

Length of Diagonal = 4 cm

4 ÷ 2 = 2 cm

Step Three: Find the area of ΔPST

b = PT = 10 cm

h = S to PT = 2 cm

A = bh / 2

A = (10)(2) / 2

A = 20 / 2

A = 10 cm²

Step Four: Find the length of Q to PT perpendicularly

Similar to step two, Q is the endpoint of one diagonal, and by definition, diagonals are perpendicular and congruent with each other. Therefore, the length of Q to PT perpendicularly is half of the diagonal.

Length of Diagonal = 4 cm

4 ÷ 2 = 2 cm

Step Five: Find the area of ΔPQT

b = PT = 10 cm

h = Q to PT = 2 cm

A = bh / 2

A = (10)(2) / 2

A = 20 / 2

A = 10 cm²

Step Six: Combine area of two triangles to find the total area

Area of ΔPST = 10 cm²

Area of ΔPQT = 10 cm²

10 + 10 = 20 cm²

Hope this helps!! :)

Please let me know if you have any questions

Answer:

⊥

Step-by-step explanation:

d and b meet at a 90 degree angle ( as shown by the box)

The lines are perpendicular (⊥)

Answer:

B

Step-by-step explanation:

A x - 36 <42 is wrong because its saying how many can be added

B x +36 < 42 this one is most likely correct because its displays x as how many can be added

C x - 36 > 42 this is wrong because the bus has less than 42 seats

D x + 36 >57 like i said cant be over 42

The inequality representing the possible number of passengers that can be added to the bus is Option(B) x + 36 < 42.

An inequality is a relation which makes a non-equal comparison between two numbers or other mathematical expressions. Inequality is used most often to compare two numbers on the number line by their size. There is always a definite equation to represent it.

Let x be the number of passengers that can be added to the bus.

It is given that the bus has less than 42 seats and 36 seats are already occupied.

The sum of the remaining seats which are to be filled by the passenger and the 36 seats which are filled, must be less than the total seats that is 42.

Therefore the inequality equation becomes,

x + 36 < 42.

Thus, the inequality representing the possible number of passengers that can be added to the bus is Option(B) x + 36 < 42.

To learn more about inequality equation, refer -

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Answer:  70  and -16

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Explanation:

For now, we'll assume x is the largest value (aka the max)

Let's sort the values from smallest to largest.

7, 20, 26, 27, 34, 41, 47, x

We see that 7 is the smallest item, so,

range = max - min = x - 7

Set this equal to 63 and solve for x

x-7 = 63

x = 63+7

x = 70

So x could be equal to 70.

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Next, we'll assume that x is the smallest value

That means the min is x and 47 is now the max

max - min = range

47 - x = 63

-x = 63-47

-x = 16

x = -16

So if x is the smallest value, then it must be -16

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Finally, we'll let x be somewhere between 7 and 47

Unfortunately, we can't pin down a specific value here since we could have lots of possible values. Three such examples are x = 8, x = 9, and x = 10. There are many others.

If your teacher is looking for 2 values only, then I would refer to the previous two sections and ignore this section entirely.

Answer:

Yes, she will be able to retrieve the item

Step-by-step explanation:

The information with regards to the research historian interest in finding a sunken treasure are;

The depth from which the equipment can recover items = 5,000 m

The speed of sound through water, v = 1,530 m/s

The time it takes the echo from the item to return to the sonar detector, t = 6.2 s

Let d, represent the depth at which the item is located

Given that an echo travels from the sonar detector to the item and back to the sonar detector, the distance traveled by the sound wave which is received as an echo by the sonar detector = 2 × d

Velocity, v = Distance/time

∴ Distance = Velocity × Time

The distance traveled by the echo = 2 × d = v × t

2 × d = v × t

∴ 2 × d = 1,530 m/s × 6.2 s

d = (1,530 m/s × 6.2 s)/2 = 4,743 m

The depth at which the item is located, d = 4,743 m is less than the maximum depth the equipment can recover items, therefore, she will be able to retrieve the item.

Answer:

60

Step-by-step explanation:

Step 1:

3 x 5 = 15

Step 2:

15 x 4 = 60

Answer:

well 3. x 5 is 15, then multiply by 4 to get 60.

Step-by-step explanation:

Answer:

hope this helps you

have a great day

Answer:

v =  14 km/h

Step-by-step explanation:

d = 0.0067[tex]v^{2}[/tex] + 0.15v

differentiate the function with respect to v to have;

d = 0.0134v - 0.15

given that the distance without skidding = 37 m (0.037 km) , then;

0.037 = 0.0134v - 0.15

0.0134v = 0.037 + 0.15

             = 0.187

v = [tex]\frac{0.187}{0.0134}[/tex]

  = 13.9552

v =  14 km/h

The speed of the car travelling would be 14 km/h to be able to stop within 37m.

Answer:

Option B

<F = 26°

<D = 64.01°

FD = 89

Answered by GAUTHMATH

For right triangle EFD,  m ∠F ≈ 26°, m ∠D ≈ 64.01° and FD = 89

The correct answer is an option (B)

It is the longest side of the right triangle.

For a right triangle,

[tex]a^{2}+ b^{2} = c^{2}[/tex], where c is hypotenuse and a, b area other two sides of the right triangle

For given example,

We have been given a right triangle EFD with hypotenuse FD.

Also, EF = 80, ED = 39

Using the Pythagoras theorem,

[tex]\Rightarrow FD^{2}= EF^{2} + ED^{2}\\\\ \Rightarrow FD^{2}= 80^{2} + 39^{2}\\\\ \Rightarrow FD^2 = 6400 + 1521\\\\ \Rightarrow FD^2 = 7921\\\\\Rightarrow FD = 89[/tex]

Consider, sin(F)

[tex]\Rightarrow sin(F)=\frac{ED}{FD} \\\\\Rightarrow sin(F)=\frac{39}{89}\\\\ \Rightarrow sin(F)=0.4382\\\\\Rightarrow \angle F=sin^{-1}(0.4382)\\\\\Rightarrow \angle F=25.98^{\circ}\\\\\Rightarrow \angle F\approx 26^{\circ}[/tex]

Now, consider sin(D)

[tex]\Rightarrow sin(D)=\frac{FE}{FD}\\\\ \Rightarrow sin(D)=\frac{80}{89}\\\\ \Rightarrow \angle D = sin^{-1}(0.8988)\\\\\Rightarrow \angle D = 64.009^{\circ}\\\\\Rightarrow \angle D \approx 64.01^{\circ}[/tex]

Therefore, for right triangle EFD,  m ∠F ≈ 26°, m ∠D ≈ 64.01° and FD = 89

The correct answer is an option (B)

Learn more about Pythagoras theorem here:

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Answer:

just add a small amount to the 2.8 and square the result

Step-by-step explanation:

x x^2

2.8 7.84

2.81 7.8961

2.82 7.9524

2.83 8.0089

2.84 8.0656

2.85 8.1225

2.86 8.1796

2.87 8.2369

Answer:

Another example of a number who's square root is greater than the number is  [tex]\sqrt{0.49}[/tex] which is 0.7

Step-by-step explanation:

This square root is larger than the number because it is a decimal. When you multiply a decimal by a decimal, the decimal point becomes greater. For example: 0.7 multiplied by 0.7 equals 0.49 which has 2 decimal places, while 0.7 only has one.

Answer:

j=|x|

Step-by-step explanation:

Answer:

[tex]\frac{1}{x} =\frac{1}{3\sqrt{8} } =\frac{1(\sqrt{8})}{3\sqrt{8}(\sqrt{8})} =\frac{\sqrt{8}}{3*8} =\frac{\sqrt{8}}{24} =\frac{\sqrt{(2)(2)(2)}}{24}=\frac{2\sqrt{2} }{2(12)} =\frac{\sqrt{2} }{12}[/tex]

Answer:

700 parts

Step-by-step explanation:

To find the total amount of parts in the shipment, all we need to do is divide.

6% = 0.06

42 / 0.06 = 700

Best of Luck!

Respuesta:

El cálculo no está bien hecho.

el cociente es 13

El resto es 29

Explicación paso a paso:

Dividendo = 445

Divisor = 32

Cociente = 14

Resto = 7

445/32 = 13,90625

El cociente = 13

Resto = (13.90625 - 13) * 32

Resto = 0.90625 * 32

Resto = 29

Por lo tanto, el cálculo no se realiza correctamente ya que el cociente es 13 y el resto es 29

Answer:

Step-by-step explanation:

Use this formula:

[tex]A(t)=P(1+\frac{r}{n})^{nt}[/tex] where A(t) is the amount after the compounding is done, P is the initial investment (our unknown), r is the interest rate in decimal form, n is the number of compoundings per year, and t is the time in years. Filling in:

[tex]520=P(1+\frac{.03}{12})^{(12)(3)}[/tex] and simplifying that a bit:

[tex]520=P(1+.0025)^{36[/tex] and a bit more:

[tex]520=P(1.0025)^{36[/tex] and even  bit more:

520 = P(1.094551401) and divide to get

P = $475.30

Answer:

Step-by-step explanation:

factor the numerical coefficients (6 and 96)

HCF 6 and 96 is 6

HCF x^10 and x^2 = x^2

HCF: 6x^2

(6* x^8*x^2 - 16*6 x^2)             Take out the highest common factor

6x^2 (x^8 - 16)

Answer:

D. Closed circle on 8, shading to the right.

Answer:

Option (B).

Step-by-step explanation:

Here there are two parallel lines c and d cuts by a transversal p.

The angles are formed as shown in diagram.

Here,

[tex]\angle 1 = \angle 7 (alternate)\\\\\angle 2 = \angle 6 (corresponding)\\\\\angle 3 = \angle 5 (alternate)\\\\\angle 5 = \angle 7 (alternate)[/tex]

So, the option (B) is correct.

Answer:

B) 9

Step-by-step explanation:

Because there's a square between the 2 angles, that means these angles are complementary (angles that add up to 90°). So:

5x - 9 + 6x = 90

11x - 9 = 90

11x = 90 + 9

11x = 99

x = 9

Answer:

B.9

Step-by-step explanation:

The way to solve this is by noticing that these angles are complementary(they add up to 90 degrees). So you add the equations together and equal them to 90. 5x-9+6x=90.Then you solve to find that x=9.

Answer:

V = 24.28 in ^3

Step-by-step explanation:

The area of the base is

A =5/2 × s × a  where s is the side length and a is the apothem

A = 5/2 ( 2.13) * .87

A = 4.63275

The volume is

V = Bh  where B is the area of the base and h is the height

V = 4.63275 ( 5.24)

V =24.27561 in^3

Rounding to the  hundredth

V = 24.28 in ^3

3c+  2=  -22

⇔3c = -22 -2

⇔3c = -24

⇔c=  -24/3

⇔c=- 8

Answer:

3c= -22-2

3c= -24

c= -24/3

c= -8

Step-by-step explanation: