Question

SOMEONE CHECK MY WORK PLEASE!!!
The coordinates A(0, 0), B(0, 4), C(3, 4) and D(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 1

It is a square But if you rotate it about the y-axis you can get a cylinder. You can get this by using the distance formula and the slope formula as a proof for this.

(0,0) ---> (0,4)
Distance formula =3
slope = Undefined

(0,4) ---> (3,4)
Distance formula =3
slope = 0

(3,4) ---> (3,0)
Distance formula =3
slope = Undefined

Answer 2

@ParthKohli @jigglypuff314

Answer 3

yes you are right. i think square and cylinder are correct answers..good job!

Answer 4

Thank you so much!! But what about my proof...

Answer 5

Dont i need to add more and is it correct on the slopes and where i put undefined.

Answer 6

u need to add one more side..(0,0) and (0,3) and the undefined part is correct..only then you will get tan theta = 90 and in a square adjacent sides are perpendicular to each other.. u must mention this point coz otherwise iif just write "all sides are equal".. it may be a rhombus as well.

Answer 7

got it?

Answer 8

Im sorry kind off can you correct it for me and ill see the changes ( Im not asking this for the answer im just a visual learner lol).

Answer 9

for how many pairs of points have u found the distance?

Answer 10

four pairs of points

Answer 11

i see only three pairs..where is the fourth?

Answer 12

Ohhh. thats why you said (0,0) and (0,3).

Answer 13

yup!

Answer 14

But i just got confused cause the question doesnt say anything about (0,3).

Answer 15

Where do i add it in?

Answer 16

(please dont leave me lol i have been stuck all day with this).

Answer 17

sry its (3,0)..typing error. and u can add iot right after ur last pair..

Answer 18

oh okay

Answer 19

good.. now how can u say its a square and not a rhombus?

Answer 20

ohh true

Answer 21

u can say that its a square coz adjacent sides are perpendicular to each other.. thats why u have found out their slopes.. thats it!

Answer 22

um by adding in the (3,0) with the (0,0) wouldnt this end up to be undefined?

Answer 23

OH

Answer 24

Looking at the attached diagram, you can get the lengths of sides of the rectangle by counting units. That is because the rectangle with the given coordinates has horizontal and vertical sides.

AB = 4 which will be the height of the cylinder and segment AB will be the axis of symmetry for the cylinder when the rotation starts.

The radius of what will be the circular base of the cylinder is 3, the radius of the base is segment AD.

Answer 25

So thats all i had to say for the question?
AB = 4 which will be the height of the cylinder and segment AB will be the axis of symmetry for the cylinder when the rotation starts.
The radius of what will be the circular base of the cylinder is 3, the radius of the base is segment AD.

Answer 26

what about the (0,0) and (3,0) he was talking about.

Answer 27

(0,0) ---> (0,4)
Distance formula =3
slope = Undefined

(0,4) ---> (3,4)
Distance formula =3
slope = 0

(3,4) ---> (3,0)
Distance formula =3
slope = Undefined

is that all wrong?

Answer 28

Can you attach the diagram to your answer?

Quadrilateral ABCD is a rectangle. In the diagram, you see it as the scored region inside the cylinder.

Answer 29

No i cant sorry. Im in FLVS, so it doesnt let me.

Answer 30

To my thinking, the question you are asked to answer with a proof is poorly written.

But, you have to submit something.

Answer 31

Yep. And that is true. So what i put previously, should i not put it in my answer at all
this:
(0,0) ---> (0,4)
Distance formula =3
slope = Undefined

(0,4) ---> (3,4)
Distance formula =3
slope = 0

(3,4) ---> (3,0)
Distance formula =3
slope = Undefined

is that all wrong?

Answer 32

A B
(0,0) ---> (0,4)
Distance formula = 4
slope = Undefined

Answer 33

oh so the first one was wrong ! thank you for noticing !!!!

Answer 34

B C
(0,4) ---> (3,4)
Distance formula =3
slope = 0

Answer 35

ohhhh

Answer 36

C D
(3,4) ---> (3,0)
Distance formula = 4
slope = Undefined

Answer 37

okay i see what you did

Answer 38

D A

(3,0) (0,0)
Distance Formula = 3
Slope is 0

Answer 39

ohhhhhhhh

Answer 40

I feel so stupid right now

Answer 41

Quadrilateral ABCD is a rectangle.

The rectangle will have axis of rotation segment AB. The length of AB is 4 and 4 is the height of the cylinder.

Segment AD has length 3 and segment AD is the radius of the base of the cylinder.

Answer 42

thank you !!!

Answer 43

>>I feel so stupid right now

No need to feel stupid. I used your work and added one more part to it.

Answer 44

ohh okay THANK YOU SO MUCH!!!

Answer 45

my final answer:

It is a square But if you rotate it about the y-axis you can get a cylinder. You can get this by using the distance formula and the slope formula as a proof for this.

A B
(0,0) ---> (0,4)
Distance formula = 4
slope = Undefined

B C
(0,4) ---> (3,4)
Distance formula =3
slope = 0

(3,4) ---> (3,0)
Distance formula =3
slope = Undefined

C D
(3,4) ---> (3,0)
Distance formula = 4
slope = Undefined

D A
(3,0) (0,0)
Distance Formula = 3
Slope is 0


Quadrilateral ABCD is a rectangle.

The rectangle will have axis of rotation segment AB. The length of AB is 4 and 4 is the height of the cylinder.

Segment AD has length 3 and segment AD is the radius of the base of the cylinder.

Answer 46

I was already your fan but i gave you a medal!!

Answer 47

Error here: It is a square But if you rotat

It is a rectangle. But .....

Answer 48

oh yeah !! Thank you !! And THANK YOU AGAIN!! its 1:41 am and i can finally go to sleep lol!

Answer 49

A square has 4 sides equal in length. This figure has two sides of 3 and two sides of 4.

It is a rectangle.

Answer 50

I gave you a medal due to the fact that i was already your fan.

Answer 51

THANK YOU!!

Answer 52

Get some rest. You are welcome.

Answer 53

:D