## anonymous one year ago Fan and medal! Triangle ABC is similar to triangle DEF. Using the image below, prove that lines BC and EF have the same slope. You must show all of your work to receive credit.

1. anonymous

2. lizz123

Step 1: Find the points for B, C , E, and F.

3. anonymous

B -2,4 C 1,1 E 4,4 F 6,2 @lizz123

4. lizz123

5. lizz123

Do you know how to use: $y=\frac{ y2-y1 }{ x2- x1 }$

6. lizz123

You can use BC first or EF first

7. anonymous

No, please explain this to me

8. anonymous

@lizz123

9. lizz123

ok using the points you just used there is an x and y part

10. lizz123

so using the points for B which: B= -2, 4 x will be -2 y will be 4

11. lizz123

12. lizz123

Technically the points from B= -2,4 it would be written like this x1=-2 y1=4

13. lizz123

Do C but instead of using x1 and y1 you have to use x2 and y2 so you can use two other numbers for x and y 2

14. anonymous

y=y2−4/x2+2

15. anonymous

y=1−4/1+2

16. anonymous

@lizz123

17. anonymous

@Hero @Here_to_Help15 @Elsa213 @EmmanuelRocksYou @inowalst @OregonDuck @demonchild99 @sammixboo @campbell_st I need some help!!

18. campbell_st

look at triangle ABC what is the length of AB what is the length of AC...?

19. campbell_st

AB is rise and AC is run Slope = rise/run

20. OregonDuck

A = (-5, 8) C = (-11, 2) x1 y1 x2 y2 slope = Y2-Y1 / X2-X1 = 2-8 / -11--5 = -6/ -11+5 = -6/-6 = 1

21. anonymous

B -2,4 C 1,1 E 4,4 F 6,2 ABC= 4.5 EFD= 2 @campbell_st that's all I know so far @OregonDuck

22. anonymous

@OregonDuck could you please explain to me how you got that? ):

23. anonymous

@Nnesha @perl @Loser66 @sammixboo @pooja195 @uri @Michele_Laino @Champion @geerky42 @Preetha @shifuyanli @Data_LG2 @tHe_FiZiCx99 @myko @Love_Ranaa Mathlete @Mehek14 Im really need some help I've been on this question for like two hours

24. anonymous

you just have to continue what you were doing :) this for the slope of BC: m=1−4/1+2 what did you get when you solve that?

25. anonymous

m= -3/3 m= -1 Is this right? @Data_LG2

26. anonymous

yes. Now do the same thing with EF

27. anonymous

y=2−4/6-4 -2/2 -1 @Data_LG2

28. anonymous

right :) Do EF and BC have the same slope?

29. anonymous

Yes off they're both -1!

30. anonymous

ofc*

31. anonymous

exactly :) your proof will be your solution in solving their slopes and you're done with it