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Angles are not drawn to scale

The depth of the mirror of the cross-section of a searchlight would be 8.33 cm if the light bub has a vertex at 3 cm and the mirror is 20 centimeters across at the origin.

A cross-section is perpendicular to the axis of the symmetry goes through the vertex of the parabola. The cross-sectional shape of the mirrored section of most searchlights or spotlights is parabolic.

Given:

a = 3

y = [tex]\frac{20}{2}[/tex] cm = 10 cm

Solution:

from the equation [tex]y^{2} = 4ax[/tex]

[tex]y^{2} = 4*3*x\\ y^{2} = 12x[/tex]

putting x, 10 cm in the equation

[tex]x=\frac{10^{2} }{12} \\\\x= \frac{100}{12} \\\\x= 8.33 cm[/tex]

thus, the depth of the mirror would be - 8.33 cm

Learn more about other problems of the parabola:

https://brainly.com/question/12793264

Answer:

x=-5

Step-by-step explanation:

[tex]\frac{x}{x+3} =\frac{5}{2} \\5x+15=2x\\5x-2x=-15\\3x=-15\\x=-15/3=-5[/tex]

Answer:

either it's 1:3 or 1:6

Step-by-step explanation:

3 students went to the zoo, and 15 students went to the aquarium.

15 plus 3 is 18.

3/18 then reduces to 1/6

therefore it is:

1:6

(before, I got my answer deleted so, maybe it is 1:3, but I solved it and got 1:6)

Answer:

higddthhgffhjkkkmjguyfddd

⇛3(3+4)

⇛9 + 12

Answer:

multiply 3 by 18

Step-by-step explanation:

1 page

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

3 minutes

Multiply the top and bottom by 18 to get to 18 pages

1*18 page

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

3*18 minutes

18 pages

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

54 minutes

Answer:

multiply 3 by 18

Step-by-step explanation:

rate = number of pages / time

rate = 1 page/3 min = 1/3 page/minute

pages = rate * time

time = pages / rate

time = 18 pages / (1/3 page/minute)

time = 18 * 3 minutes

Answer: multiply 3 by 18

Answer:

g: -7/10 or -0.7

Step-by-step explanation:

[tex]6g+5=-2\left(1+2g\right)[/tex]

Apply the distributive law:-

[tex]-2\left(1+2g\right)[/tex]

[tex]=-2-4g[/tex]

[tex]6g+5=-2-4g[/tex]

Now, we´ll Subtract 5 from both sides :-

[tex]6g+5-5=-2-4g-5[/tex]

[tex]6g=-4g-7[/tex]

Add 4g to both sides :-

[tex]6g+4g=-4g-7+4g[/tex]

[tex]10g=-7[/tex]

Now, divide both sides by 10:-

[tex]\frac{10g}{10}=\frac{-7}{10}[/tex]

[tex]g=-\frac{7}{10}[/tex]

OAmalOHopeO

Answer:

The answer simplified would be:

-4y^2+3y+5

If you combine the like terms, you will get this answer.

You have to add 8y^2 to -12y^2 and you get -4y^2.

Hope this helps you! :)

Answer:

10 people buy slushies and the price of each is lb. They have already spent w on food. How much did they spend on slushies.

Step-by-step explanation:

Answer:

6

Step-by-step explanation:

the solution in photo :)

Answer:

6

Step-by-step explanation:

→ Prime factorise each number

12 = 2² × 3 ⇒ 2 × 2 × 3

18 = 2 × 3² ⇒ 2 × 3 × 3

24 = 2³ × 3 ⇒ 2 × 2 × 2 × 3

→ Find which number there are in each one

2 and 3

→ Multiply them together

2 × 3 = 6

Answer:

C. [tex]g\,\circ \, f (x) =g(f(x))[/tex]

Step-by-step explanation:

Let be [tex]f(x) = x-500000[/tex] the excedent on annual sales and [tex]g(x) = 0.2\cdot x[/tex] the bonus factor, to determine the bonus amount a composition of [tex]f(x)[/tex] is [tex]g(x)[/tex] must be done. That is:

[tex]g\,\circ \, f (x) =g(f(x))[/tex]

Hence, the right answer is C.

Answer:

No, it's just maximum of two tables that lost balloon so there is no way it affected each table.

Step-by-step explanation:

Number of balloons purchased= x

Number of tables = 8.

Each table has = x/8 balloons

If 2 balloons pop.

Let's assume it's just from a table

That table has( x/8 -2)

If it's from 2 table

The two table has

(X/8-1) for both tables

But the total balloon remaining = x-2

There is no particular equation that can describe the gallon on each table because it's only two balloons that popped.

Answer:

That expression is not true. To evenly distribute the balloons you use x/8. Then you subtract 2 balloons from that total amount. The subtraction must be done after the division. There will not be the same number of balloons at each table.

Step-by-step explanation:

It was the sample answer.

Answer:

1.83

Step-by-step explanation:

The standard deviation of given data set rounded to the hundredth place is 2.55

Given data set is: 9, 11, 12, 16

The mean of the data set is 12.

The formula for standard deviation is written as:

[tex]\sigma = \sqrt{{\sum^\:n}_{i=1}{\dfrac{(x_i-\overline{x})^2}{n}}\\[/tex]

here n = 4 and x assumes 9, 11, 12 and 16 and mean is 12, thus putting values in the given formula,

[tex]\sigma = \sqrt{\dfrac{[(9-12)^2 + (11-12)^2 + (12-12)^2 + (16-12)^2]}{4}}\\\sigma = \sqrt{\dfrac{[3^2 + 1^2 + 4^2]}{4}}\\\sigma = \sqrt{\dfrac{26}{4}}\\\sigma = \sqrt{6.5}\\\sigma = 2.549..\\\sigma \approx 2.55[/tex]

Thus, standard deviation of given data set rounded to the hundredth place is 2.55

Learn more here:

https://brainly.com/question/12402189

Answer:

7

Step-by-step explanation:

you would divide by 7 then times by 6

Answer:

216

Step-by-step explanation:

Volume of a rectangular prism = area of base * depth

Area of base: 72

Depth: 3

Volume = 72 * 3 = 216

Answer:

No, because 6² + 8² ≠ 12²

Step-by-step explanation:

In a right angled triangle,

Perpendicular² + Base² = Hypotenuse² (pythagoras theorem)

But in the given triangle; 6² + 8² ≠ 12²

36 + 64 ≠ 144

100 ≠ 144

Perpendicular² + base² ≠ hypotenuse²

Thus the given triangle is not right angled.

Answer: Yes, Substitution property is the correct option.

Step-by-step explanation:

Given: m∠A+m∠B =70° ...(i),  m∠X=m∠A

Then, substitute m∠X for m∠A in (i) , we get

m∠X+m∠B =70°

So, the correct option is "Substitution property"

Answer:

5cm

Step-by-step explanation:

A=4πr2 =  100πcm2

r = 5

Answer:

Step 2.

Step-by-step explanation:

Given the two equations,

Equation A: y = 10 - 2z

Equation B: 5y = 2 - 4z solved by a student, we are to determine the step where the student made an error in his/her calculation. Let's follow the steps;

Step 1: multiply equation A by -5. The essence of this is to be able to cancel out one of the variables and calculate for the other variable. On multiplication we have;

y = 10 - 2z × (-5)

5y = 2 - 4z × (1)

_____________________

-5y = -5(10-2z) .... A

5y = 2 - 4z..... B

Step 2: simplify equation A by opening the bracket.

-5y = -5(10)+5(2z)

-5y = -50+10z

The equations become;

-5y = -50+10z .... A

5y = 2 - 4z..... B

It can be seen that her simplified expression does not tally with what we got i.e -5y = -50+10z. This was the step the student made the first error.

Since this student step is wrong, the remaining calculation will be wrong.

Let us fix the calculation steps now.

We will continue from the previous step.

Step3: Add equation A and B in step 2 together.

-5y+5y = (-50+2)+(10z-4z)

0 = -48+6z

Step 4: Add 48 to both sides:

0+48 = -48+6z+48

48 = 0+6z

48 = 6z

Step 5: Divide both sides by 6

48/6 = 6z/6

6 = z

z= 6

Hence, the value of z = 6 not 12 and the student made his/her first error in step 2.

Answer: lenght x widthx height

Step-by-step explanation:

Answer:

[tex]\sqrt{12}=2\sqrt{3}[/tex]

[tex]\sqrt{18} = 3\sqrt{2}[/tex]

[tex]\sqrt{24}=2\sqrt{6}[/tex]

[tex]\sqrt{72}=6\sqrt{2}[/tex]

Step-by-step explanation:

Hi there!

[tex]\sqrt{12}[/tex]

To simplify a square root, check if the radicand has any perfect square factors. For example, 12 can be rewritten as 4*3:

[tex]=\sqrt{4*3}\\=\sqrt{4}*\sqrt{3}[/tex]

4 is a perfect square. Its square root is 2:

[tex]=2*\sqrt{3}\\=2\sqrt{3}[/tex]

[tex]\sqrt{18} \\= \sqrt{9*2} \\= 3\sqrt{2}[/tex]

[tex]\sqrt{24} \\=\sqrt{4*6}\\=2\sqrt{6}[/tex]

[tex]\sqrt{72} \\=\sqrt{36*2} \\=6\sqrt{2}[/tex]

I hope this helps!

Answer:

7.6 cm²

Step-by-step explanation:

Area of rectangle= l x w

3 x 4 = 12 cm

Area of circle= πr²

π x 2.5²= 19.625

Area of shaded= Area of circle - area of rec

19.625- 12= 7.625 cm²

≈7.6

I HOPE THIS HELPED

Answer:

572 7s are needed to be added together

Step-by-step explanation:

Basically, what we are asked here is the multiple of 7 which is closest to but above 4,000

Then, from this multiple , the number of 7s which are added together to give it is our answer.

By multiplication; 7 * 572 = 4,004

This is the closest multiple of 7 to 4000 which is also above it.

So the fewest number of 7s which we can add together is 572

Answer:

3. 150.72 in²

4. 535.2cm²

Step-by-step Explanation:

3. The solid formed by the net given in problem 3 is the net of a cylinder.

The cylinder bases are the 2 circles, while the curved surface of the cylinder is the rectangle.

The surface area = Area of the 2 circles + area of the rectangle

Take π as 3.14

radius of circle = ½ of 4 = 2 in

Area of the 2 circles = 2(πr²) = 2*3.14*2²

Area of the 2 circles = 25.12 in²

Area of the rectangle = L*W

width is given as 10 in.

Length (L) = the circumference or perimeter of the circle = πd = 3.14*4 = 12.56 in

Area of rectangle = L*W = 12.56*10 = 125.6 in²

Surface area of net = Area of the 2 circles + area of the rectangle

= 25.12 + 125.6 = 150.72 in²

4. Surface area of the net (S.A) = 2(area of triangle) + 3(area of rectangle)

= [tex] 2(0.5*b*h) + 3(l*w) [/tex]

Where,

b = 8 cm

h = [tex] \sqrt{8^2 - 4^2} = \sqrt{48} = 6.9 cm} (Pythagorean theorem)

w = 8 cm

[tex]S.A = 2(0.5*8*6.9) + 3(20*8)[/tex]

[tex]S.A = 2(27.6) + 3(160)[/tex]

[tex]S.A = 55.2 + 480[/tex]

[tex]S.A = 535.2 cm^2[/tex]

Answer:

same day = 25

advanced = 40

Step-by-step explanation:

Let a = advanced tickets

s = same day tickets

s+a = 65

25a+35s = 1875

Multiply the first equation by -25

-25s -25a = -1625

Add this to the second equation

25a+35s = 1875

-25a -25s= -1625

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

     10s = 250

Divide each side by 10

10s/10 = 250/10

s =25

Now find a

s+a = 65

25+a = 65

a = 40

Answer: same day = 25

advanced = 40

Answer:

1

Step-by-step explanation:

x +2y=1

2y+x  will equal 1

use the formula a^3+b^3=(a+b)^3-3ab(a+b)

in above question assume (a+b) as a and 1 as b

take help of file above

Answer:

Zero

Step-by-step explanation:

2+6=8 which means it can't be. It has to be a length higher than 10

Answer:

See explanation

Step-by-step explanation:

When we have a positive number and a negative number, let's imagine it with a number line.

<-----------0----------->

If we have the positive number 1:

<-----------0--1-------->

And we want to subtract 1 from it, the number would move to the left

1 - 1 = 0

<-----------0----------->

However, if we were to subtract a negative number, they are opposites. It can't move to the left because that's what a positive number does. The only other way to go: right.

1 + -1 = 2

<-----------0--1--2----->

Hope this helped!

answer

x = {-5, -⅓}

explanation

[tex]3 {x}^{2} + 16x + 5 = 0[/tex]

[tex]3 {x}^{2} + 15x + x + 5 = 0[/tex]

[tex]3x(x + 5) + 1(x + 5) = 0[/tex]

[tex](x + 5)(3x + 1) = 0[/tex]

[tex]x = - 5 \: or \: - \frac{1}{3} [/tex]

[tex]x = \{ - 5 \: , - \frac{1}{3} \}[/tex]

HOPE IT HELPS...