Surveys, observational studies, and experiments are examples of

Answer:

35,691

Step-by-step explanation:

First step, look at the diagram and you see that you have a sphere and a cone.

The total surface area of a sphere is

[tex]A = 4\pi r^{2} \\A = 4\pi 39^{2} \\A = 19,113[/tex]

Since you only have half of a sphere, the surface area is 9,556.5

The surface area of the cone is

[tex]A = pi r(r+\sqrt{h^{2}+r^{2} }) A = \pi39(39+\sqrt{42^{2} +39^{2} } \\A=11,800[/tex]

You don't need the bottom of the cone however as it is connected to the half sphere.

So substract the area of a circle with a radius of 39 from the product of 19,113 + 11,800

The area of the circle is 4,778

Answer:

Z = 65 Y = 115

Step-by-step explanation:

z+115 = 180

z=65

y + 65 +100+80= 360

y+245 = 360

y=115

Answer:

y = 115°

z = 65°

Step-by-step explanation:

*IMPORTANT* Straight line = 180° & Squares = 360°

1) 180° - 115° = 65°

z = 65°

2) 360° - 100° - 80° - 65° = 115°

Also, interior angles = exterior angles

Answer:

48 in³

Step-by-step explanation:

the volume = ½×3×4 × 8 = 48 in³

Answer:

6 seconds after launch.

Step-by-step explanation:

You should make sure  there aren't odd symbols in your question when you post it.

Assuming it is just the equation -5x^2 + 20x + 60, if you graph it you can see the path of the ball.  at x=0 this is the starting point It then hits the ground when it touches the x axis.  So this is finding zeroes of a quadratic.

You could do this several ways; find a way to factor it, guess and check, the quadratic formula or completing the square.  I will complete the square as that is what I am most used to.  If you would like to see another let me know.

The first step in completing the square is making sure the x^2 has a coefficient of 1, so now it has -5 so we have to factor out -5 from the equation.

-5x^2+20x+60 = -5(x^2 - 4x - 12)

Now you only really need to focus on the factored expression, but I will continue writing everything.  The next step is to find (b/2)^2 where b is the coefficient of the x term.  In this case -4.  so (b/2)^2 = (-4/2)^2 = 4.

Again, focusing on x^2 - 4x - 12 you want to add and subtract (b/2)^2 from that expression.  since you are adding and subtracting you are not changing the value, but we can use this.

-5(x^2 - 4x - 12) = -5(x^2 - 4x - 12 + 4 - 4)

Here you want to rearrange it a bit.  Originally c was the constant term, -12, now you want it to be the positive (b/2)^2, which is positive 4. also you can combine the two other constant terms.  the original c and -(b/2)^2, but I will hold off for now so I don't do too much at once.

-5(x^2 - 4x - 12 + 4 - 4) = -5(x^2 - 4x + 4 - 12 - 4)

Now you focus on x^2 - 4x + 4.  Hope fully you recognize this is the same as (x-2)^2.  This always happens at this step of the process.  also notice -2 = b/2.  Using only variables here are the first steps.

ax^2 + bx + c

a(x^2 + (b/a)x + (c/a))

a(x^2 + (b/a)x + (c/a) + (b/(2a))^2 - (b/(2a)^2)

a(x^2 + (b/a)x + (b/(2a))^2 + (c/a) - (b/(2a))^2)

a((x + b/(2a))^2 + (c/a) - (b/(2a))^2)

Again, being able to make x^2 - 4x + 4 into (x-2)^2 or x^2 + (b/a)x + (b/(2a))^2 into (x + b/(2a))^2 willa lways happen.  this is because if you expand (x + b/(2a))^2 you always get x^2 + (b/a)x + (b/(2a))^2.

Now I would combine the -12-4

-5(x^2 - 4x + 4 - 12 - 4) = -5((x - 2)^2 - 12 - 4) = -5((x - 2)^2 - 16)

If you redistribute the -5 you get vertex form, but I am going to stop here  because I will just undo that in the next step.  So this is the form you want.  Finally we can find when it equals 0.  So, you set this equal to 0 and use algebra to solve.

-5((x - 2)^2 - 16) = 0

Divide both sides by -5

(x-2)^2 - 16 = 0

add 16 to both sides

(x-2)^2 = 16

Take the square root of both sides, but also count botht he positive and negative version of the answer.  the reason is both 2 and -2 squared get you 4.

x - 2 = +/-4

I am using +/- to indicate I am using both positive and negative 4.  Now though add 2 to both sides.  since you have +/- 4 you are going to get two different results.  -4+2 and 4+2

x = -2 and 6.

now, the question wants times after x=0 (the start) so you only get 6.  so x=6, or in other words 6 seconds after launch.

Let me know if you have any questions.

Answer:

6

Step-by-step explanation:

sorry no step by step explanation because I’m in a rush please mark me as brainliest bye have a great day !!! :D

Answer:

1. The theoretical probability of rolling an even number and flipping heads is 25%.

2. The experimental probability of rolling a 1 and flipping tails is 15%.

3. The experimental probability of flipping heads is 40%.

4. I think around 7%.

5. I would expect to roll 3 and land on heads 8 times.

Step-by-step explanation:

I am not sure about number 4.

Have a nice day!

Ask me if you need my work. :-)

Answer:

not really sure

but I'll try for you

Answer:

1,800$

Step-by-step explanation:

25% is 1/4th of the total amount. So...

Divide 2,400$ by 4 and get 600

Now, subtract 600 from 2,400.

Note:

Pls notify me if my answer is incorrect for the other users that will see this response. Thank you.

-kiniwih426

Answer:

cosθ = sinθ/tanθ

Step-by-step explanation:

tanθ = sinθ/cosθ (Given)

cosθ(tanθ) = sinθ (Mulitplied cosθ on both sides)

cosθ = sinθ/tanθ (Divided tanθ on both sides)

Answer:

Escribí esto, así que espero que quede claro.

Step-by-step explanation:

Maybe 256x square 8

Answer:

A. y = -(x + 5)^2 + 4

Step-by-step explanation:

After a small online search, I've found that the options are:

A. y = -(x + 5)^2 + 4

B. y = -(x - 5)^2 + 4

C. y = -(x + 5)^2 - 4

D. y = -(x - 5)^2 - 4

For a quadratic equation with a vertex at the point (h, k) is written as:

y = a*(x - h)^2 + k

Where a is the leading coefficient.

So, if here we have the vertex at (-5, 4)

y = a*(x - (-5))^2 + 4

y = a(x + 5)^2 + 4

Then the correct option is the first one, where a = -1, then the correct option is A.

Answer:

hey mate

the question is not understandable

Answer:

A -  y = cos(x-1)

Step-by-step explanation:

This is what it looks like when you graph y = cos(x-1). It matches the graph on your question exactly, this graph is just using trig concepts.

Please give me brainliest if my answer was right. :)

Answer:

Angle F

Step-by-step explanation:

=====================================================

Explanation:

We see that angle A = angle E as shown by the arc marking. The tickmark says that side AB is the same length as side EF.

In the letter sequences "AB" and "EF", erase the first letters A and E to be left with B and F. This is one way to show how angle B pairs with angle F, and that is enough to show the two angles are congruent.

Answer:

Step-by-step explanation:

Because 3x10=30 and 31 is greater than 30 by 1 more.

It's not. 3 times 10 is 30.

30<31

Answer:

c is the and

no worries thank you to each of the Fourth of that mother you have any other questions please contact me

Answer:

56 cups of water

Step-by-step explanation:

Katrina drinks 0.5 gallons of water per day

We have 7 days in a week, hence, the number of gallons of water she drinks per week is calculated as:

1 day = 0.5 gallons

7 days = x

Cross Multiply

1 day × x = 7 days × 0.5 gallons

x = 7 days × 0.5 gallons/1 day

x = 3.5 gallons

Note that 16 cups = 1 gallon

The number of cups of water she drinks per week is

1 gallon = 16 cups

3.5 gallons = x

Cross Multiply

1 gallons × x = 3.5 gallons × 16 cups

x = 3.5 gallons × 16 cups/1 gallons

x = 56 cups

Therefore, Katrina drinks 56 cups of water in a week

Answer:

your answer is y=-8 for sure

Answer:

23

Step-by-step explanation:

I DID 7*3+2 & GOT 23

Answer:

[tex]x=\pm \sqrt{11} \\y=-4.[/tex]

Step-by-step explanation:

[tex]\left \{ {{3x^2+4y=17} \atop {2x^2+5y=2}} \right. \\\\Then\\\\\left \{ {{2 \times (3x^2+4y)=2 \times 17} \atop {3\times(2x^2+5y)=3\times2}} \right. \\\\\left \{ {{6x^2+8y=34 \quad (1)} \atop {6x^2+15y=6\quad (2)}} \right.\\\\(1)-(2) \Rightarrow -7y=28 \Rightarrow y =-4.\\Since \: \: 2x^2+5y=2 \Rightarrow 2x^2=2-5y\\\Rightarrow 2x^2=2+20=22\\\Rightarrow x^2=22:2=11\\\Rightarrow x=\pm \sqrt{11}.[/tex]

Given:

The table of value and y is inversely proportional to square of x.

To find:

The value of c and d.

Solution:

It is given that y is inversely proportional to square of x. So,

[tex]y\propto \dfrac{1}{x^2}[/tex]

[tex]y=k\dfrac{1}{x^2}[/tex]               ...(i)

Where, k is the contant of proportionality.

From the given table it is clear that [tex]y=4[/tex] and [tex]x=3[/tex]. Putting these values in (i), we get

[tex]4=k\dfrac{1}{3^2}[/tex]

[tex]4=\dfrac{k}{9}[/tex]

[tex]4\times 9=k[/tex]

[tex]36=k[/tex]

Putting [tex]k=36[/tex] in (i), we get

[tex]y=36\dfrac{1}{x^2}[/tex]

[tex]y=\dfrac{36}{x^2}[/tex]             ...(ii)

Putting [tex]x=5,y=c[/tex] in (ii), we get

[tex]c=\dfrac{36}{(5)^2}[/tex]

[tex]c=\dfrac{36}{25}[/tex]

Putting [tex]x=d,y=2[/tex] in (ii), we get

[tex]2=\dfrac{36}{d^2}[/tex]

[tex]d^2=\dfrac{36}{2}[/tex]

[tex]d^2=18[/tex]

Taking square root on both sides, we get

[tex]d=\pm \sqrt{18}[/tex]

[tex]d=\pm 3\sqrt{2}[/tex]

Therefore, the required values are [tex]c=\dfrac{36}{25}[/tex] and [tex]d=\pm 3\sqrt{2}[/tex].

Answer:

8.238

Step-by-step explanation:

it might not be right, but it was not fast either XDDD

dang, i took to long to tell u

:)

Answer:

2.03% Rate of Population Growth.

Step-by-step explanation:

According to the Question,

Given, In 2006 the population was 1148 and in 2014 the population was 1348.

2006⇒2014  (8 Years)

So, [tex]1148 * (1+\frac{x}{100} )^{8} = 1348[/tex]

[tex](1+\frac{x}{100} ) = \sqrt[8]{1.1742}[/tex]

(1 + x/100) = 1.0202

x/100 = 0.020276

x = 2.03% Rate of Population Growth

Answer:

Step-by-step explanation:

Draw two lines vertically down from side "A" to "B"...you now have three objects ... to triangles, and one rectangle.... the area of the rectangle is "AH"...now you have two triangles, that have area 1/2 base*height... the height is "H" and the base .... well it is (B-A)/2... so the area of the two triangles are ..... (2)*(1/2)*((B-A)/2)* H.... The total area is .... AH + (2)*(1/2)*((B-A)/2)* H .... 2* 1/2 = 1 so now we have AH +   ((B-A)/2)* H .... to help see this let us write it as AH + H(B-A)/2 .. expand the right H.... AH + BH/2 - AH/2.......

you end up with : AH - AH/2 + AB/2 ...

AH - AH/2 =  AH/2

BH/2 = BH/2

final answer : AH/2 + BH/2

factor out the 1/2 and H ..... 1/2 H (A+B)

Answer:

See Explanation

Step-by-step explanation:

The question is incomplete; However, one can deduce from the options that the question refers to percentage change.

I will give two illustrations that shows how to calculate percentage change.

Illustration 1

Consider goods x with the following price change.

[tex]Old = \$45[/tex]

[tex]New = \$55[/tex]

The percentage change is:

[tex]\%Change = \frac{New - Old}{Old} * 100\%[/tex]

[tex]\%Change = \frac{55-45}{45} * 100\%[/tex]

[tex]\%Change = \frac{10}{45} * 100\%[/tex]

[tex]\%Change = \frac{1000}{45} \%[/tex]

[tex]\%Change = 22.22\%[/tex]

This means there is a 22.22% increase

Illustration 2

Consider goods x with the following price change.

[tex]Old = \$45[/tex]

[tex]New = \$35[/tex]

The percentage change is:

[tex]\%Change = \frac{New - Old}{Old} * 100\%[/tex]

[tex]\%Change = \frac{35-45}{45} * 100\%[/tex]

[tex]\%Change = \frac{-10}{45} * 100\%[/tex]

[tex]\%Change = -\frac{1000}{45} \%[/tex]

[tex]\%Change = -22.22\%[/tex]

The negative sign indicates percentage decrease

So, this means there is a 22.22% decrease

Answer:

tn=t¹+d(n-1)

Step-by-step explanation:

d=common difference

t¹=1st term

n= the nth term

Answer:

Step-by-step explanation:

Sequence, so easiest way is difference between any 2 consecutive numbers

Neg 3 to 2, difference is 5

2 to 7, difference is 5

7 to 12 , difference is 5

So sequence result for n

= starting point + (n-1)(5)

Eg 2nd, N= 2

Starting point is neg 3

Sequence = -3 + 2-1 (5) = -3 + 5 = 2

9th, n = 9

-3 + 8(5)

-3 + 40

37

Answer:

9°

Step-by-step explanation:

m / sin L M = o / sin L O

41/sin L M = 98/sin 22°

=> sin L M = 41×sin 22°/98

= 41×0,3746 / 98

= 0,1567

so, L M = sin~¹ 0,1567 = 9°