## rajfk35 3 years ago Observe parallelogram ABCD plotted on the coordinate plane below. Part I: Provide the coordinates of a parallelogram A’B’C’D’ that is congruent to parallelogram ABCD. Explain why these figures are congruent. (4 points) Part II: Provide the coordinates of a parallelogram A’’B’’C’’D’’ that is similar to parallelogram ABCD. Explain why these figures are similar. (6 points)

1. rajfk35

2. rajfk35

3. Grazes

Do you need help with both parts?

4. DarlingDare

This is geometry, isn't it?

5. Grazes

Yeah. Coordinate Geometry.

6. rajfk35

yes i need help with both parts

7. Grazes

Do you know what a Dilation and Translation is?

8. rajfk35

translation is it when you move the figure to the opposite side from where it is

9. DarlingDare

And what about a dilation, rajfk?

10. Grazes

Translation isn't the opposite side one. Isn't reflection the one that you described?

11. rajfk35

i do not know that one Darlin

12. DarlingDare

It's when the figure gets bigger or smaller by a certain factor.

13. Grazes

So anyway, translation is when you add random numbers to both x and y. An example of that would be (x,y)--> (x+1,y+3)

14. Grazes

Dilation is when something gets smaller or bigger by a constant like Darlin said. An example, if the constant is 2 would be (x,y)-->(2x,2y)

15. rajfk35

okay

16. Grazes

So for the first part, translations make geometric objects stay congruent

17. Grazes

Because the distances are all still the same

18. rajfk35

okay i get that part now

19. DarlingDare

Couldn't have said it better myself :)

20. Grazes

So you find the coordinates for all 4 points and add or subtract whatever you want to them to get the first part

21. Grazes

Shift all the points one column to the right if you're feeling lazy

22. Grazes

For the second part, what you want to do is get the coordinates and multiply x and y by 2. Then you plot the new coordinates you found

23. DarlingDare

Lazy doesn't get u anywhere.... I know that from experience, but it can work. Just make sure you double check your work...

24. Grazes

Lazy gets you somewhere if you're good at it. But that's just for math. I fell asleep for the math placement test and got double period algebra. But I got an 100 average for it

25. DarlingDare

XD

26. Grazes

raj. How are you holding up?

27. DarlingDare

Raj? You there?

28. rajfk35

yes i am

29. Grazes

Are you done? Or do you still need me?

30. rajfk35

no i still need you

31. Grazes

What's up?

32. rajfk35

part two

33. DarlingDare

Can't you do a proportion for the second part to see that they are similar?

34. Grazes

Well, yeah. But that's just for checking it. You would be guessing and checking to get the coordinates

35. Grazes

okay. Raj. Give me the coordinates for point A I'm too lazy to find it

36. DarlingDare

hmm... good to know... then I have been doing that part wrong for a long time.....

37. Grazes

Alright. You're taking too long to find it for me. so A is (-7,3). What you do is make up a random constant like 2. So (x,y)->(2x,2y), right?

38. Grazes

So then you plug x and y in to get (2[-7],2[3]) or (-14,6)

39. Grazes

Which means that A11 is (-14,6). Understand?

40. DarlingDare

Raj?

41. DarlingDare

Well, I understood, but I don't know if Raj did...

42. Grazes

Darlin. what are you taking for math next year?

43. DarlingDare

Algebra 2

44. DarlingDare

I am finishing up geometry this week

45. DarlingDare

Right now, I'm on geometric proofs. I don't like it at all...

46. Grazes

You have class now? But it's the summer break. And mind looking at this? http://openstudy.com/study#/updates/50207fade4b0fef6292c85b8

47. DarlingDare

Yes, I want to skip a grade in the math department..... and sure!!!!!