Solve the simultaneous equations.
Show all your working.
3x + 4y = 14
5x+2y=21

Explanation:

P(T = 1) is the notation that means "The probability of getting exactly one tail". The table shows 3/8 in the bottom row, under the "1" in the top row. So that's why P(T = 1) = 3/8

Or it might make more sense to say P(one tail) = 3/8 so we don't have too many equal signs going on.

9514 1404 393

Answer:

  B

Step-by-step explanation:

In order for the matrix to represent the equations, the coefficients in the equations need to match the terms in the matrix. That is only the case for choice B.

__

Details are important in math.

Sample variance = 228.408

Standard deviation = 15.113

The well formatted frequency table has been attached to this response.

To calculate the sample variance and standard deviation of the given grouped data, follow these steps:

i. Find the midpoint (m) of the class interval.

This is done by adding the lower bounds and upper bounds of the class intervals and dividing the result by 2. i.e

For class 0 - 9, we have

m = (0 + 9) / 2 = 4.5

For class 10 - 19, we have

m = (10 + 19) / 2 = 14.5

For class 20 - 29, we have

m = (20 + 29) / 2 = 24.5

For class 30 - 39, we have

m = (30 + 39) / 2 = 34.5

For class 40 - 49, we have

m = (40 + 49) / 2 = 44.5

This is shown in the third column of the attached table.

ii. Find the product of each of the frequencies of the class intervals and their corresponding midpoints. i.e

For class 0 - 9, we have

frequency (f) = 13

midpoint (m) = 4.5

=> f x m = 13 x 4.5 = 58.5

For class 10 - 19, we have

frequency (f) = 7

midpoint (m) = 14.5

=> f x m = 7 x 14.5 = 101.5

For class 20 - 29, we have

frequency (f) = 10

midpoint (m) = 24.5

=> f x m = 10 x 24.5 = 245

For class 30 - 39, we have

frequency (f) = 9

midpoint (m) = 34.5

=> f x m = 9 x 34.5 = 310.5

For class 40 - 49, we have

frequency (f) = 11

midpoint (m) = 44.5

=> f x m = 11 x 44.5 = 489.5

This is shown in the fourth column of the attached table.

iii. Calculate the mean (x) of the distribution i.e

This is done by finding the sum of all the results in (ii) above and dividing the outcome by the sum of the frequencies. i.e

x = ∑(f x m) ÷ ∑f

Where;

∑(f x m) = 58.5 + 101.5 + 245 + 310.5 + 489.5 = 1205

∑f = 13 + 7 + 10 + 9 + 11 = 50

=> x = 1205 ÷ 50

=> x = 24.1

Therefore, the mean is 24.1

This is shown on the fifth column of the attached table.

iv. Calculate the deviation of the midpoints from the mean.

This is done by finding the difference between the midpoints and the mean. i.e m - x where x = mean = 24.1 and m = midpoint

For class 0 - 9, we have

midpoint (m) = 4.5

=> m - x = 4.5 - 24.1 = -19.6

For class 10 - 19, we have

midpoint (m) = 14.5

=> m - x = 14.5 - 24.1 = -9.6

For class 20 - 29, we have

midpoint (m) = 24.5

=> m - x = 24.5 - 24.1 = 0.4

For class 30 - 39, we have

midpoint (m) = 34.5

=> m - x = 34.5 - 24.1 = 10.4

For class 40 - 49, we have

midpoint (m) = 44.5

=> m - x = 44.5 - 24.1 = 20.4

This is shown on the sixth column of the attached table.

v. Find the square of each of the results in (iv) above.

This is done by finding (m-x)²

For class 0 - 9, we have

=> (m - x)² = (-19.6)² = 384.16

For class 10 - 19, we have

=> (m - x)² = (-9.6)² = 92.16

For class 20 - 29, we have

=> (m - x)² = (0.4)² = 0.16

For class 30 - 39, we have

=> (m - x)² = (10.4)² = 108.16

For class 40 - 49, we have

=> (m - x)² = (20.4)² = 416.16

This is shown on the seventh column of the attached table.

vi. Multiply each of the results in (v) above by their corresponding frequencies.

This is done by finding f(m-x)²

For class 0 - 9, we have

=> f(m - x)² = 13 x 384.16 =  4994.08

For class 10 - 19, we have

=> f(m - x)² = 7 x 92.16 = 645.12

For class 20 - 29, we have

=> f(m - x)² = 10 x 0.16 = 1.6

For class 30 - 39, we have

=> f(m - x)² = 9 x 108.16 = 973.44

For class 40 - 49, we have

=> f(m - x)² = 11 x 416.16 = 4577.76

This is shown on the eighth column of the attached table.

vi. Calculate the sample variance.

Variance σ², is calculated by using the following relation;

σ² = ∑f(m-x)² ÷ (∑f - 1)

This means the variance is found by finding the sum of the results in (vi) above and then dividing the result by one less than the sum of all the frequencies.

∑f(m-x)² = sum of the results in (vi)

∑f(m-x)² = 4994.08 + 645.12 + 1.6 + 973.44 + 4577.76 = 11192

∑f - 1 = 50 - 1 = 49         {Remember that ∑f was calculated in (iii) above}

∴ σ² = 11192 ÷ 49 = 228.408

Therefore, the variance is 228.408

vii. Calculate the standard deviation

Standard deviation σ, is calculated by using the following relation;

σ =√ [ ∑f(m-x)² ÷ (∑f - 1) ]

This is done by taking the square root of the variance calculated above.

σ = [tex]\sqrt{228.408}[/tex]

σ = 15.113

Therefore, the standard deviation is 15.113

Answer:

option B : 31.4 cm

Step-by-step explanation:

Given radius , r = 5cm

Circumference = [tex]2 \pi r[/tex]

                       = 2 x 3.14 x 5

                       =10 x 3.14

                       = 31.4 cm

Answer:

b. 31.4

Step-by-step explanation:

The radius of the circle can be plugged into C=(pi)2r. So 5x2= 10 and 10x(pi)= 31.4

Answer:

No, you cannot have a negative distance.

Step-by-step explanation:

No, you cannot have a negative distance.

Let's say you were asked for the absolute value of -4. How many units is -4 away from 0? The answer would be 4. There is no negative distance from 0.

Hope this helps, please mark brainliest! :)

Answer:

3x4 +x3+ 15x2+30x-14

Step-by-step explanation:

Answer:

Subtract x x from both sides of the equation. 8y=20−x 8 y = 20 - x. Divide each term by 8 8 and simplify.

Solve for x 2x-4y=4. 2x−4y=4 2 x - 4 y = 4. Add 4y 4 y to both sides of the equation. 2x=4+4y 2 x = 4 + 4 y. Divide each term by 2 2 and simplify.

Answer:

acute triangle

Step-by-step explanation:

First find the other angle

The sum of the angles is 180

x+65+60  = 180

x + 125 = 180

x = 180-125

x = 55

All three angles are different so all three side lengths are different

All the angles are less than 90 so all the angles are acute

This is an acute scalene triangle

Answer:

im is 55 so the only correct option is c

Step-by-step explanation:

hope this helps! have a great day!!

Answer:

,(i) answer is 203,918

(ii)answer is227,306.36

Answer:

98

Step-by-step explanation:

x(o) + 1(o)  = 180(o)

∠2° = ∠x°

∠1° = ∠3°

Answer:

angle 2 is 82 also and angle 3 and 4 is 180 - 82 = 98

Answer:

D

Step-by-step explanation:

the domain of the function is the boundaries in the X condition. using the graph we see X starts at 2 and ends at 7 so the domain is

[tex]2 \leqslant x \leqslant 7[/tex]

Answer:

D. 5 + c

Step-by-step explanation:

( - 5 - c ) ( - 1 )

use distributive property ; to multiply -5 and - c by -1.

Answer:

I think it's approximately 44°

[tex]h(-3) - h( - 2) = - \frac{5}{ 8} \\ \\ [/tex]

Step-by-step explanation:

[tex]\boxed{h(x) = \frac{2 {x}^{2} - x + 1}{3x - 2}}[/tex]

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

[tex]h(2) = \frac{2 {(4)} - 2 + 1}{6 - 2} [/tex]

[tex]h(2) = \frac{ 8 - 1}{4} [/tex]

[tex]h(2) = \frac{7}{4}[/tex]

[tex]h( - 3) = \frac{2 {( - 3)}^{2} - ( - 3) + 1}{3( - 3) - 2} \\ h( - 3) = \frac{2 (9) + 3 + 1}{ - 9- 2} \\ h( - 3) = \frac{18 + 4}{ - 11} \\ h( - 3) = \frac{22}{ - 11} \\ h(-3) = -2[/tex]

[tex]h( - 2) = \frac{2 {( - 2)}^{2} - ( - 2) + 1}{3( - 2) - 2} \\ h( - 2) = \frac{2 (4) + 2+ 1}{- 6 - 2} \\ h( - 2) = \frac{8 + 3}{- 8} \\ h( - 2) = \frac{11}{- 8} [/tex]

[tex]h(3) - h( - 2) = -2 - \frac{11}{- 8} \\ h(3) - h( - 2) =-2 + \frac{11}{ 8} \\ h(3) - h( - 2) = \frac{-2}{1}+ \frac{11}{ 8} \\ h(3) - h( - 2) = \frac{-16}{8} + \frac{11}{ 8} \\ h(3) - h( - 2) = \frac{-16+11}{8} \\ h(3) - h( - 2) = \frac{-5}{8} \\ - \frac{5}{ 8} [/tex]

Answer:

-3

Step-by-step explanation:

My knowledge ;D

Answer:

Mary's friend Larry is taller by 15cm.

Step-by-step explanation:

First look for the bigger number.

Then subtract the smaller number from the bigger number.

Answer:

C ,D , E just follow it . thank me later if its right

Answer:

E

Step-by-step explanation:

(10+7)(50+1)

=17×51

=867

Answer:

Yes

Step-by-step explanation:

875 roses / 7 plants per row

875 / 7 = 125 rows, which is a whole number, meaning nothing is left over

Answer:

4-12x

Step-by-step explanation:

opening the brackets;

(-6×-2/3)- 12x

-2×-2 -12x

4-12x

Answer:

4 - 12x

Step-by-step explanation:

We can find an equivalent expression by distributing

-6(-⅔+2x)

Distribute by multiplying -6 times what's inside of the parenthesis ( -2/3 and 2x )

-6 * -⅔ = 4

-6 * 2x = -12x

We would be left with 4 - 12x

Answer:

Table could be first x = 2, y = 4, then x = 4, y = 8. It is proportional because both (x,y) values equal 1/2. The equation is x = 1/2y. Last, the table could be the same, or you could do first, x = 6, y = 12, then x = 12, y = 24, because they still equal 1/2.

Step-by-step explanation:

Answer:

100/8 = 12.5 (s)

Step-by-step explanation:

hmm bro

Answer:

[tex]{ \boxed{ \tt{formular : { \bf{ \green{time = \frac{distance}{speed} }}}}}} \\ time = \frac{100}{8} \\ { \boxed{time = 12.5 \: seconds}} \\ \\ { \underline{ \blue{ \tt{becker \: jnr}}}}[/tex]

Answer:

(a) Amplitude = 4

(b) [tex]T = \frac{2\pi}{3}[/tex] --- Period

(c)

[tex]C = \frac{\pi}{3}[/tex] --- phase shift

[tex]D =1[/tex] --- vertical shift

Step-by-step explanation:

Given

[tex]f(x) = -4\cos(3x - \pi) + 1[/tex]

Rewrite the function as:

[tex]f(x) = -4\cos(3(x - \frac{\pi}{3}) + 1[/tex]

Solving (a): The amplitude

A cosine function is represented as:

[tex]f(x) = A\cos[B(x - C)] + D[/tex]

Where:

[tex]|A| \to Amplitude[/tex]

So, in this equation (by comparison):

[tex]|A| = |-4|[/tex]

[tex]|A| = 4[/tex]

The amplitude is 4

Solving (b): The period (T)

This is calculated as:

[tex]T = \frac{2\pi}{B}[/tex]

By comparison:

[tex]B =3[/tex]

So:

[tex]T = \frac{2\pi}{3}[/tex]

Solving (c): The shift

The phase shift is C

The vertical shift is D

By comparison:

[tex]C = \frac{\pi}{3}[/tex] --- phase shift

[tex]D =1[/tex] --- vertical shift

Answer:

[tex]2x + 8[/tex]

Step-by-step explanation:

Area of triangle equal

[tex] \frac{b \times h}{2} = a[/tex]

where b is the base and h is the height.

Plug in what we know.

[tex] \frac{b \times 6x}{2} = 6 {x}^{2} + 24x[/tex]

Multiply 2 by both sides.

[tex]b \times 6x = 2(6 {x}^{2} + 24x)[/tex]

Divide 6x by both sides.

[tex]b = \frac{12 {x}^{2} + 48x }{6x} = 2x + 8[/tex]

Answer:

$3.53 per lb of salami

Step-by-step explanation:

0.75 lb of salami for $2.65

The price per of salami will be :

0.75 lb = $2.65

1 lb = x

Using cross multiplication :

0.75 * x = $2.65 * 1

0.75x = $2.65

Divide both sides by 0.75

0.75x / 0.75 = $2.65 / 0.75

x = $3.533

This means that :

The price per unit of salami is $3.53

Answer:

0.75 lb of salami for $2.65 is $3.53 per lb of salami.

Respuesta:

3215360 cm³

Explicación paso a paso:

Dado que :

Radio = 160/2 = 80 cm

Altura, h = 160 cm

Volumen de un cilindro = πr²h

Volumen del cilindro = π * 80² * 160

Volumen = 3215360 cm³

Answer:

A

Step-by-step explanation:

42-14=28

Answer:

A. 42 and 14

Step-by-step explanation:

first number = x

second number = y

x - y = 28

3x - x = 28

(y is now x because it says the second number is whatever x was, but three times less)

x = 14

3(14) - (14) = the original number, 28

Your Answer is in the above image.

Answer:

45

hope this helps

Answer:

45

Step-by-step explanation:

9x5=45