## iheartfood 3 years ago Question inside :)

1. iheartfood

|dw:1352783711712:dw|

2. iheartfood

graph A, graph B (top is A, bottom is B)

3. iheartfood

4. iheartfood

idk, do u get it?

5. hartnn

can u find intercepts ?

6. iheartfood

idk how to,.. can u pls show me?

7. hartnn

for y-intercept, put x=0

8. iheartfood

what do i plug that into?

9. hartnn

y=a(0+b)^(1/3)

10. iheartfood

and i get y=0?

11. hartnn

so y-intercept is ab^(1/3) now since a and b are positive, y-intercept is also positive.

12. iheartfood

okay, so what does that mean??

13. hartnn

which rules out A,C

14. iheartfood

okay so how do i figure out between B and D?

15. hartnn

find x-intercept

16. iheartfood

how do i do that?

17. hartnn

put y=0 in that equation

18. iheartfood

which one? the one we just found?

19. iheartfood

so i get this? 0=ab^(1/3) ??

20. hartnn

the original one 0=a(x+b)^(1/3) so x= ?

21. iheartfood

so i get 0=(ax+ab)^1/3 ??? and idk how to find x= tho :(

22. hartnn

0=a(x+b)^(1/3) (x+b) = 0 (because a is positive and not 0, x+b must be 0) so x=-b means x - intercept is negative

23. hartnn

which graph among, B and d has x-intercept negative ?

24. iheartfood

okay, so hmmm is it B then?? the one i attached??

25. hartnn

yes, its b

26. iheartfood

okay thanks!!! :)

27. hartnn

DID U UNDERSTAND HOW ITS DONE ?

28. iheartfood

yeah :) find the intercepts and substitute and see whether it positive or negative... and u first find the first one and rule it out, then u narrow the answers down based on that intercept... then you find the next intercept and see if its pos or neg. and based on that u find ur graph. is that right? did i understand it correctly? :)

29. hartnn

oh,yes ! :)

30. iheartfood

yayy!! :) thank youuu :)

31. hartnn

what about finding intercepts, did u get how to find them ?

32. iheartfood

i think so... i do get confused about it tho sometimes... :( could u pls give me a summary on how to find them? so i understand them more clearly??