Mrs . Johnson has a total of 30 students in her class , The ratio of boys to girls is 2:3 , how many does Mrs. Johnson have in her class ?

Answer:

D (7a-3)/4

Step-by-step explanation:

7a – 4b = 3

Subtract 7a from each side

7a-7a – 4b = 3-7a

-4b = 3 -7a

Divide by -4

-4b/-4 = (3-7a)/-4

b = (7a-3)/4

Answer:

b = (7a - 3)/4

Step-by-step explanation:

7a - 4b = 3

=> -4b = 3 - 7a

=> b = (3 - 7a)/(-4)

=> b = -(3 - 7a)/4

=> b = (-3 + 7a)/4

=> b = (7a - 3)/4

Answer:

x=24

Step-by-step explanation:

3/4(x-8)=12

Multiply each side by 4/3

4/3*3/4(x-8)=12*4/3

x-8 = 16

Add 8 to each side

x-8+8 = 16+8

x=24

Answer:

x = 24

Step-by-step explanation:

Essentially, you need to break this apart.

You need to isolate the x to figure it out with division or something.

To isolate, you need to get rid of the numbers around it.

To get rid of the 3/4, you can convert it to a decimal to make it easier, and then divide both sides by 0.75 to get rid of it on the x's side.

You now have

x-8 = 12/0.75

You can quickly punch the right side into a calculator to make it easier.

x - 8 = 16

You then add 8 to both sides to finish off the x, to get

x = 24

Step-by-step explanation:

soln no. k

LHS: cosø√1+cot^2ø

= cosø×cosecø

= cosø× 1/sinø

= cosø/sinø

= cotø

=√cosec^2-1. [: cot^2ø=cosec^2ø-1

according to equation

sending the (^2) will be

root over in another Sid]

= RHS proved

for number m take the help of the pic

Answer:

3,6

Step-by-step explanation:

Answer:

6.08

Explainion: is shown in picture above

Answer:

18.8

Step-by-step explanation:

You just add the two lengths and then do pythagorean theory to get the length of the hypotenuse. Then you add them all together to get 18.8. Hope this helps.

Answer:

SA = 37.5 units^2

Step-by-step explanation:

2 1/2 = 2.5

the Surface Area of the cube

SA = 6a^2

SA = 6(2.5)^2

SA = 6(6.25)

SA = 37.5 units^2

Answer:

it can be 5 from my side is that right

Answer:

is ur question right

Step-by-step explanation:

is ur question right

is ur question right

is ur question right

Answer:

y is -1

Step-by-step explanation:

[tex]4x + 2y = 14 - - - (a) \\ x - 2y = 6 - - - (b)[/tex]

(a) + (b):

[tex]5x = 20 \\ x = 4[/tex]

therefore:

[tex]x - 2y = 6 \\ 4 - 2y = 6 \\ 2y = - 2 \\ y = - 1[/tex]

Answer:

y must be -1

Step-by-step explanation:

We are given the system of linear equations

4x + 2y = 14

 x - 2y = 6

and need to find the value of y.  Combining the two equations yields

5x = 20, and so we know that x must be 4.

If x is 4, then the second equation becomes 4 - 2y = 6, or -2y = 2.

Then y must be -1.

Step-by-step explanation:

Hi there!

From the given Question, we have;

Diameter (d) = 34ft

Height (h) = 16ft

Now;

Radius (r) = d/2

= 34/2

= 17 ft

Now;

Volume (v) = 1/3(πr²h)

= 1/3(3.14 * 17² * 16) ft³

= 4839.78 ft³

Therefore, the Volume is 4839.78 ft³.

Hope it helps!

Answer:

There are 0.454 kg in one pound.

So, in 120 pounds there are 0.454 x 120 kgs.

This is equal to 54.48, and the answer is 54.48 kg.

Let me know if this helps!

Answer:

[tex]916.11\:ft^{3}[/tex]

Step-by-step explanation:

Volume of the hexagonal pyramid =  [tex]1/3\times (area\: of \: hexagonal\:base)\times height[/tex]

Here sides of hexagonal base = 9 ft

So, Area of hexagon = [tex]6\times \frac{\sqrt{3} }{4} a^{2}[/tex]

[tex]6\times \frac{\sqrt{3} }{4} \times 9 \times 9[/tex]

[tex]= 210.5[/tex]

Height is given, 13 ft

So, volume = [tex]1/3\times 210.5\times 13[/tex]

[tex]= 916.11\: ft^{3}[/tex]

OAmalOHopeO

Step-by-step explanation:

from the second:

A=[3 -1]. -2B

[-5 0]

input this into 1

2([3 -1]) -(2B) -B =[1 3]

([-5 0]). [0 5]

[6 -2] -4B-B=[1 3]

[-10 0]. [0 5]

-5B=[1 3] -[3 -1]

[0 5]. [-5 0]

-5B= [1-3 3+1]

[0+5 5+0]

B= [-2/5 4/5]

[1 1]

A=[(19/5) (3/5)]

[-3. 2]

using the formula I derived

that's how I got A

Answer:

Step-by-step explanation:

Let the number be x

14 ÷ x = [tex]\frac{14}{x}[/tex]

Answer:

14 / x

Step-by-step explanation:

quotient = /

14 = 14

a number = the variable, let's call it x

Brainliest please!

Answer:

The correct choice is option C. 4xy√3y

Step-by-step explanation:

√12x^2y^3 + 2xy√3y

√12x^2y^3 = 2√3 xy√y

2xy√3y = 2√3 xy√y

2√3 xy√y +  2√3 xy√y

= 4√3 xy√y

= 4xy√3y

Answer:

4 x n= y²

You have to find the product of a number and 4

Answer:

√4×n

Step-by-step explanation:

4*n squared so n stands for number

Answer:

$2.3

Step-by-step explanation:

Let the price of the orange juice be x

We know he bought 2 bottles of orange juice = 2x

He also bought an apple juice which is 0.35$ less than orange juice, so the price of the apple juice would be = (x-0.35)

The sum of these two purchases = $6.55

2x + (x-0.35) = 6.55

2x + x - 0.35 = 6.55

3x = 6.55 + 0.35

3x = 6.9

x = 6.9/3

x = 2.3

So the bottle of orange juice costs $2.3

answered by g a u t h m a t h

Answer:

498

Step-by-step explanation:

For the blue block: 4(7x2) + 2(2x2) = 56 + 8 = 64

For green block: 4(12x7) + 2(7x7) = 336 +98 = 434

434 + 64 = 498

Answer:

C

Step-by-step explanation:

A and B are examples of direct variations because there is a nonzero constant k in each such that y=kx. A's k=1/12 while B's k=12.

D is not a direct or inverse variation because of the plus/minus constant.

C is an inverse variation because it has form y=k/x where k is nonzero. This k=12.

Answer:

C

Step-by-step explanation:

The equation representing inverse variation is

y = [tex]\frac{k}{x}[/tex] ← k is the constant of variation

The only equation that fits this description is

y = [tex]\frac{12}{x}[/tex] → C

Answer:

x = 1 and y =5

Step-by-step explanation:

[tex]8x -2y= -2\\Divide by -2\\-4x+y = 1\\add 4x\\y= 1+4x\\[/tex]

Substitute this value of y in the next equation.

[tex]9x+5(1+4x) = 34\\9x+5+20x=34\\29x+5=34\\29x=29\\x=1[/tex]

Solve for y using x.

[tex]y=4x+1\\y=4(1)+1\\y=5[/tex]

Answer:

9

Step-by-step explanation:

5/3 (x + 1/2) = 95/6

5/3 × 1/2 = 5/6

5/3x + 5/6 = 96/6

         -5/6     -5/6

---------------------------

5/3x = 90/6

5/3x = 15

------    ----

5/3      5/3

x  = 9

Answer:

19.4

Step-by-step explanation:

Perimeter = 53 feet

P = 2L + 2H

L = 7.1 feet

2L + 2W = 53 feet

2*7.1 + 2w = 53

14.2 + 2w = 53

2W = 53 - 14.2

2W = 38.8

W = 38.8/2

W = 19.4

H = 19.4

Answer:

25 = 141 + 159/2

Step-by-step explanation:

Answer:

30

Step-by-step explanation:

So we begin by assigning variables to each side with:

DE = x

EF = y

DF = z

Now we start listing a system of equations from what is given:

x+y+z=81

x=2y

x-4=z

Once we solve that with substitution, we get the result of:

x=34

y=17

z=30.

Since z is the length of DF, the length of DF is 30.

I hope this helped! :D

We want to compute the probability P(A or B) because we could either solve it following path A, path B, or doing both paths.

P(A) = 1/3

P(B) = 2/5

P(A and B) = P(A)*P(B)  assuming A,B are independent

P(A and B) = (1/3)*(2/5)

P(A and B) = 2/15

--------

P(A or B) = P(A) + P(B) - P(A and B)

P(A or B) = 1/3 + 2/5 - 2/15

P(A or B) = 5/15 + 6/15 - 2/15

P(A or B) = (5 + 6 - 2)/15

P(A or B) = 9/15

We could reduce this to 3/5, but it appears your teacher has chosen not to.

[tex]\sf11 {x}^{2} - 3 {x}^{2} \\ [/tex]

They are like terms so you can just easily subtract them directly.

[tex]\sf11 {x}^{2} - 3 {x}^{2} \\ = \boxed{\bf8x {}^{2}} [/tex]

Hope it helps.

RainbowSalt2222

[tex]\\ \sf\longmapsto 11x^2-3x^2[/tex]

[tex]\\ \sf\longmapsto (11-3)x^2[/tex]

[tex]\\ \sf\longmapsto 8x^2[/tex]

Answer:

95.2 is not an integer

and other are integers