## nuccioreggie one year ago Triangle PQR is transformed to triangle P'Q'R'. Triangle PQR has vertices P(3, −6), Q(0, 9), and R(−3, 0). Triangle P'Q'R' has vertices P'(1, −2), Q'(0, 3), and R'(−1, 0). Plot triangles PQR and P'Q'R' on your own coordinate grid. Part A: What is the scale factor of the dilation that transforms triangle PQR to triangle P'Q'R'? Explain your answer. (4 points) Part B: Write the coordinates of triangle P"Q"R" obtained after P'Q'R' is reflected about the y-axis. (4 points) Part C: Are the two triangles PQR and P''Q''R'' congruent? Explain your answer. (2 points)

1. triciaal

@chris00 thanks I won't be able to complete pressed for time

2. anonymous

|dw:1444396883679:dw|

3. nuccioreggie

ok

4. triciaal

did you plot the points?

5. nuccioreggie

yes

6. nuccioreggie

7. triciaal

to reflect across the y-axis each point (x, y) goes to (-x, y)

8. triciaal

congruent means same compare the lengths and angles

9. anonymous

do you know how to calculate scale factors @nuccioreggie

10. triciaal

scale factor is the ratio of the sides from

11. nuccioreggie

no

12. anonymous

you can pick any point to determine the scale factor

13. nuccioreggie

ok

14. anonymous

scale factor = new image/ old image

15. nuccioreggie

So for Part A?

16. anonymous

P'(1, −2) (new image) old image P(3, −6))

17. nuccioreggie

um uhhh i sthat for part A?

18. anonymous

you can choose the x or y-coordindate to solve for it

19. anonymous

scale factor = 1/3

20. nuccioreggie

ok can you explain the answer for part A in 1 comment please

21. anonymous

i just did...

22. nuccioreggie

ohhhh lol im so sorrry so scale factor = 1/3 is the answer

23. anonymous

a) scale factor = new image/old image Pick a point, so P. P is the old image. P' is the new image. to determine the scale factor we can either use the corresponding x co-ordinate or y-coorindates. using the co-ordinates P'(1, −2) (new image) old image P(3, −6)) therefore using x co-orindate scale factor = P'/P = 1/3 or using y co-orindate scale factor = P'/P = -2/-6=1/3 therefore scale factor = 1/3 we can see this seems right because the new image is smaller than the old image

24. anonymous

good?

25. nuccioreggie

wow lol yea thanks so what about B and C?

26. anonymous

yep ok

27. anonymous

if we want to reflect it in the y axis, |dw:1444397999471:dw|

28. anonymous

as triciall said each point (x, y) goes to (-x, y)

29. nuccioreggie

oh ok so what will the answer for letter B will be?

30. anonymous

Triangle P'Q'R' has vertices P'(1, −2), Q'(0, 3), and R'(−1, 0). Therefore, P"Q"R" have verticies P''(-1,-2) Q'' (0,3) R''(1,0)

31. anonymous

|dw:1444398231371:dw|

32. nuccioreggie

ok soooo i get that the answer for C?

33. anonymous

B) since y-reflection means each point (x, y) goes to (-x, y) Therefore, Triangle P'Q'R' has vertices P'(1, −2), Q'(0, 3), and R'(−1, 0). Therefore, P"Q"R" have verticies P''(-1,-2) Q'' (0,3) R''(1,0)

34. anonymous

the diagram is used for C

35. anonymous

|dw:1444398545805:dw|

36. nuccioreggie

37. anonymous

C) Triangles are congruent when they have exactly the same three sides and exactly the same three angles So no triangles PQR and P''Q''R'' are not congruent

38. nuccioreggie

thank you

39. anonymous

np

40. anonymous

i think i get a fan after that ahah

41. nuccioreggie

can you help me with like 2more questions?

42. anonymous

sorry, i have to go to sleep. its past midnight >.<

43. anonymous

good luck

44. nuccioreggie

preciate it