Question

help plz

Answer 1

The coordinates A(0, 0), B(0, 5) and C(3, 0) are graphed and connected together. What 3-dimensional shape will be created when this shape is rotated about the y-axis? Provide an explanation and proof for your answer to receive full credit.

Answer 2

@yoongi

Answer 3

help plz

Answer 4

A great tool for graphing this would be Desmos, if you haven't already used it. It should be able to help you visualize what the pre-image of the shape (before rotation) will look like. https://www.desmos.com/calculator

Answer 5

can u still help me

Answer 6

It looks like the shape's pre-image will be a triangle with the right angle at the origin. What would happen if you rotated this shape 360 degrees?

Answer 7

i will be a cone

Answer 8

it

Answer 9

Correct!

Answer 10

thanks

Answer 11

No problem!

Answer 12

i have 2 more question if you dont mind

Answer 13

I'll answer them the best I can.

Answer 14

Which of these countries has the greatest population density? Which has the least? Provide an explanation and proof for your answer to receive full credit.

Answer 15

Country Population
(1997 estimate) Area
(square km)
U.S. 272,648,000 9,364,520
Romania 22,609,000 237,391
Ghana 18,339,000 237,533

Answer 16

I guess I'm just not really sure what that question is trying to ask.

Answer 17

Country
Population Area square km)
U.S. 272,648,000 9,364,520
Romania 22,609,000 237,391
Ghana 18,339,000 237,533

Answer 18

is that a better chart

Answer 19

Which of these countries has the greatest population density? Which has the least? Provide an explanation and proof for your answer to receive full credit

Answer 20

I'm assuming it's asking you to find the number of people per square kilometer. I'm not ENTIRELY sure what to do here, but I'm assuming you could simply divide the population by the number of square kilometers (the area) to get that information.

Answer 21

okk

Answer 22

For example, the US would be 272,648,000 / 9,364,520 = 29.115.

Answer 23

ok

Answer 24

the last question

Answer 25

Pyramid A is a square pyramid with a base side length of 14 inches and a height of 6 inches. Pyramid B has a volume of 3,136 cubic inches. How many times bigger is the volume of pyramid B than pyramid A? Give your answer as a percent. Provide an explanation and proof for your answer to receive full credit.

Answer 26

Do you know how to calculate the volume of a square pyramid?

Answer 27

V=bh1/3 i believe

Answer 28

The formula is \[\frac{ 1 }{ 3 } b ^{2} h\] or \[b ^{2} \frac{ h }{ 3 }\]

Knowing this, what would you get for the volume of the first square pyramid?

Answer 29

14^3 6/3

Answer 30

v=1372

Answer 31

That's b squared, not b cubed.

Answer 32

ok hold up let me add it again

Answer 33

v=98

Answer 34

I think you're getting caught up somewhere in the calculation. Let's take this step by step.

Answer 35

14*14=196 6/3=2 196/2=98

Answer 36

\[b ^{2} \frac{ h }{ 3 }\]

\[14^{2} \frac{ 6 }{ 3 }\]

\[196(\frac{ 6 }{ 3 }) = ? ^{3}\]

Answer 37

Ah, you're making the mistake of dividing 14 squared by six thirds instead of multiplying them.

Answer 38

ook

Answer 39

v=392

Answer 40

Good! :) Now, to calculate percent change, you would start by finding the difference between the two volumes (or the increase).

The formula to find the increase is...

\[Increase = New - Old\]

Answer 41

In this case, it would be Pyramid B - Pyramid A.

Answer 42

Er, I apologize. The other way around, I believe.

Answer 43

3,136-392= 2744

Answer 44

^^

Answer 45

Then, the formula to find percent change is \[change = (\frac{ increase }{ original })(100)\]

Answer 46

2744 2744/3136 (100)

Answer 47

87.5% is that correct

Answer 48

@nerdyotter is this correct

Answer 49

before u leave