how would you do the same on a graph paper, without using the computer tools? thanks

For those who are not good at visualizing rotations Rotate 90 degrees- (x,y) changes to (-y,x) EX: (2,3) rotated is (-3,2) Rotate 180 degrees: (x,y) changes to (-x,-y) EX: (2,3) is rotated to (-2,-3) Rotate 270 degrees: (x,y) changes to (y,-x) EX: (2,3) is rotated to (3,-2) These are general rules for the change in coordinates while doing rotations. Hope this helps someone. Thanks, Mik

Instead of rotating 270 degree counter clock wise. If you rotate it 90 degrees clockwise, would that also be correct? Because they both will land on the same position.

They are considered "co-terminal" angles of rotation, so they will look the same but are technically not the same.

The video is for doing the problems in Khan academy, but how do i solve it in paper and pencil. Do you have a video for that?

Try this video: https://www.khanacademy.org/math/geometry/hs-geo-transformations/hs-geo-rotations/v/points-after-rotation. It shows how to do it manually. There are similar videos for reflections &co too.

We can tell easily that what is 90 degrees,180degrees,270 degrees and 360 degrees in the rotation but what if the question had said rotate it by 253 degrees or 233 degrees?

Here is a video that makes it appear pretty easy with a protractor and a ruler. http://www.bing.com/videos/search?q=how+easy+is+it+to+rotate+a+figure+by+x+degrees&view=detail&mid=1A8C560DBEAD2CA958301A8C560DBEAD2CA95830&FORM=VIRE

*urgent My question in my book is asking us to descibe in full, like they shows three triangles, P,Q,R which are drawn on a Cartesian plane. Then the question say : Q is the image of P under a transformation M. Describe in full the transformation. *I don't understand why they ask us to describe the transformation and what answers I should write ? Thank you. *urgent

You have to decide whether the transformation is an enlargement, a reflection or a rotation. Then you have to say: For an enlargement: An enlargement scale factor ? about centre of enlargement ? For a reflection: Reflection in the line <equation of the line eg, y = x> For a rotation: Rotation clockwise/anticlockwise by an angle of ?? degrees about point ? As you haven't given a diagram, you're going to have to decide which of these to use and find the missing values!

Main content

Performing rotations

Name: Performing rotations
Uploaded: 2015-05-06T00:33:59Z
Description: Sal shows how to perform a rotation on a pentagon using our interactive widget!

Google Classroom

Sal shows how to perform a rotation on a pentagon using our interactive widget!

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Hafsa Kaja Moinudeen
Posted 9 years ago. Direct link to Hafsa Kaja Moinudeen's post “how would you do the same...”
how would you do the same on a graph paper, without using the computer tools?
thanks
Button navigates to signup pageComment on Hafsa Kaja Moinudeen's post “how would you do the same...”
(18 votes)
Answer
- Mik
  Posted 8 years ago. Direct link to Mik's post “For those who are not goo...”
  For those who are not good at visualizing rotations
  
  Rotate 90 degrees- (x,y) changes to (-y,x)
  EX: (2,3) rotated is (-3,2)
  
  Rotate 180 degrees: (x,y) changes to (-x,-y)
  EX: (2,3) is rotated to (-2,-3)
  
  Rotate 270 degrees: (x,y) changes to (y,-x)
  EX: (2,3) is rotated to (3,-2)
  
  These are general rules for the change in coordinates while doing rotations.
  
  Hope this helps someone.
  
  Thanks,
  Mik
  Comment on Mik's post “For those who are not goo...”
  (25 votes)
Tony Huang
Posted 9 years ago. Direct link to Tony Huang's post “Instead of rotating 270 d...”
Instead of rotating 270 degree counter clock wise. If you rotate it 90 degrees clockwise, would that also be correct? Because they both will land on the same position.
Button navigates to signup pageButton navigates to signup page
(8 votes)
Answer
- Thomas B
  Posted 9 years ago. Direct link to Thomas B's post “They are considered "co-t...”
  They are considered "co-terminal" angles of rotation, so they will look the same but are technically not the same.
  Button navigates to signup page
  (8 votes)
raisazarin2003
Posted 8 years ago. Direct link to raisazarin2003's post “The video is for doing th...”
The video is for doing the problems in Khan academy, but how do i solve it in paper and pencil. Do you have a video for that?
Button navigates to signup pageButton navigates to signup page
(4 votes)
Answer
- light city
  Posted 8 years ago. Direct link to light city's post “Try this video: https://w...”
  Try this video: https://www.khanacademy.org/math/geometry/hs-geo-transformations/hs-geo-rotations/v/points-after-rotation. It shows how to do it manually. There are similar videos for reflections &co too.
  Comment on light city's post “Try this video: https://w...”
  (2 votes)
Inshirah Samo
Posted 9 years ago. Direct link to Inshirah Samo's post “How do I do the rotation ...”
How do I do the rotation practically, on a graph paper with a protractor?
Button navigates to signup pageButton navigates to signup page
(4 votes)
Answer
16OGRONKIEWICZ
Posted 9 years ago. Direct link to 16OGRONKIEWICZ's post “He doesn't really explain...”
He doesn't really explain how he rotated it 270 degrees.
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(4 votes)
Answer
- Olivia Konell
  Posted 7 years ago. Direct link to Olivia Konell's post “So rotating a shape by 27...”
  So rotating a shape by 270 degrees clockwise is the same thing as rotating a shape by 90 degrees counterclockwise. And rotating a shape by 270 degrees counterclockwise is the same thing as rotating a shape by 90 degrees clockwise. If you know how to rotate a shape by 90 degrees, then just remember that you can rotate a shape by 270 degrees in the opposite dirrection. I hope that clears up any confusion you had about rotating a shape by 270 degrees! Let me know if you have any more questions related to this topic!
  Button navigates to signup page
  (1 vote)
Whispers (Skylar)
Posted 8 years ago. Direct link to Whispers (Skylar)'s post “What happens when i get a...”
What happens when i get a weird angle?
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(1 vote)
Answer
mas6237
Posted 7 years ago. Direct link to mas6237's post “it's still a little weird...”
it's still a little weird to me
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(2 votes)
Answer
- Phi Pip
  Posted 7 years ago. Direct link to Phi Pip's post “Don`t worry, you will get...”
  Don`t worry, you will get used to it quickly if you practice a bit.
  Button navigates to signup page
  (1 vote)
CoolDUDE
Posted 7 years ago. Direct link to CoolDUDE's post “We can tell easily that w...”
We can tell easily that what is 90 degrees,180degrees,270 degrees and 360 degrees in the rotation but what if the question had said rotate it by 253 degrees or 233 degrees?
Button navigates to signup pageButton navigates to signup page
(1 vote)
Answer
- David Severin
  Posted 7 years ago. Direct link to David Severin's post “Here is a video that make...”
  Here is a video that makes it appear pretty easy with a protractor and a ruler.
  http://www.bing.com/videos/search?q=how+easy+is+it+to+rotate+a+figure+by+x+degrees&view=detail&mid=1A8C560DBEAD2CA958301A8C560DBEAD2CA95830&FORM=VIRE
  Comment on David Severin's post “Here is a video that make...”
  (2 votes)
Caryen
Posted 9 years ago. Direct link to Caryen's post “*urgent My question in my...”
*urgent My question in my book is asking us to descibe in full, like they shows three triangles, P,Q,R which are drawn on a Cartesian plane. Then the question say :
Q is the image of P under a transformation M. Describe in full the transformation.
*I don't understand why they ask us to describe the transformation and what answers I should write ?
Thank you. *urgent
Button navigates to signup pageButton navigates to signup page
(1 vote)
Answer
- Reesharr
  Posted 9 years ago. Direct link to Reesharr's post “You have to decide whethe...”
  You have to decide whether the transformation is an enlargement, a reflection or a rotation. Then you have to say:
  For an enlargement: An enlargement scale factor ? about centre of enlargement ?
  For a reflection: Reflection in the line <equation of the line eg, y = x>
  For a rotation: Rotation clockwise/anticlockwise by an angle of ?? degrees about point ?
  
  As you haven't given a diagram, you're going to have to decide which of these to use and find the missing values!
  Comment on Reesharr's post “You have to decide whethe...”
  (2 votes)
Toni Garcia
Posted 8 years ago. Direct link to Toni Garcia's post “How do you know what poin...”
How do you know what points to bring the shape to for when you rotate it?
Button navigates to signup pageComment on Toni Garcia's post “How do you know what poin...”
(1 vote)
Answer

Video transcript

- [Voiceover] Use the "Rotate" tool to find the image of pentagon CDEFG, that's this irregular pentagon over here, when rotated 270 degrees about the point negative two comma three. The direction of rotation by a positive angle is counter-clockwise. So it's counter-clockwise. All right. Rotate tool, to rotate around negative two comma three. So let's click on "Rotate," and then we want to go to the point, they said rotate around the point negative two comma three. So I move this, to x equals negative two, y equals three. That's what we want to rotate around, and we want to rotate 270 degrees. So this is maybe the part that takes the most visualization. If we rotate 90 degrees, that would be going from, if we think about this arrow, actually, let me just do it. So, if I move this arrow up here, I have rotated 90 degrees, positive 90 degrees, we're moving counter-clockwise. Now if I move it over here, we have rotated 180 degrees, and now I move it down here. I have now rotated it 270 degrees. If they said 360, we would get back to where we started. So this is 270 degrees, just like that. And, we're done. Let's check our answer, if we got it right.

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Video transcript