pooja195 one year ago Can someone please check these? Just need to know whether my answers are correct or incorrect.(need help with #9) http://prntscr.com/8atxmk 8.QTN 9.not sure 10.Point N 11.Point L

1. jim_thompson5910

#11 is incorrect

2. jim_thompson5910

you should get a line or line segment for #11

3. jim_thompson5910

for #9, list 4 points such that they all do NOT lie on the same flat surface

4. pooja195

#11 would be line LM right? and #9 would be... P,Q,T,N ?

5. jim_thompson5910

|dw:1440989885495:dw|

6. jim_thompson5910

|dw:1440989933352:dw|

7. jim_thompson5910

plane LMN is the front face |dw:1440989980794:dw| this face is visible

8. jim_thompson5910

plane QLS is hidden and it's the left face |dw:1440990010268:dw|

9. jim_thompson5910

what points do these two planes have in common?

10. pooja195

Q,L,S?

11. jim_thompson5910

just Q and L, not S

12. jim_thompson5910

|dw:1440990090664:dw|

13. jim_thompson5910

so segment QL is the intersection of those two planes

14. jim_thompson5910

ie the corner edge where they meet

15. pooja195

ah ok got it thanks :)

16. pooja195

and is #9 correct?

17. jim_thompson5910

|dw:1440990197545:dw|

18. jim_thompson5910

Q,T,N all lie on the front plane, while P is not on that same plane. So it appears they are noncoplanar BUT notice how they all lie on the "floor" or bottom plane/face |dw:1440990328881:dw|

19. pooja195

so they are coplanar.....but there are no other points that fit what the book wants! ;-;

20. jim_thompson5910

why not move from point P and move upward? |dw:1440990416684:dw| and pick on S instead

21. jim_thompson5910

or you can change N to M

22. jim_thompson5910

there are other ways to do it as well

23. pooja195

ok makes sense thanks :)

24. jim_thompson5910

you're welcome