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## anonymous one year ago I need help with math please wait while I type the equation into the comments.

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1. anonymous

$(-27)^{\frac{ 2 }{ 3 }}$

2. anonymous

It's multiple choice a. -9 b. 9 c. 81 (I thought it was -9 but that turned out wrong)

3. anonymous

@AutumnRoseT thanks but I need to actually know how to do it and I don't need to graph it

4. deana99

I can help

5. anonymous

OK thank you @deana99 please do.

6. anonymous

Look, I know the answer is nine but I just need to know how to figure that out.

7. amistre64

the top of the fraction tells us the power, the bottom tell us the root

8. amistre64

what is (-27)^2

9. anonymous

729

10. amistre64

good now we root it $\sqrt[3]{729}$

11. anonymous

I don't know how to do that

12. amistre64

2/3 power of 2, root of 3

13. amistre64

well, you can formulate a table of perfect cubes maybe ... and compare

14. amistre64

what is 10^3?

15. anonymous

300

16. amistre64

no, 10*10*10 is not 300

17. Here_to_Help15

hint 100*10= ?

18. anonymous

i mean 1000

19. Here_to_Help15

Ding ding :)

20. amistre64

1000 yes, and 729 is less than that, so we are less then 10^3 what is 5^3?

21. anonymous

125

22. anonymous

ok so it's nine

23. anonymous

because nine cubed is 729

24. amistre64

and 125 is less then 729 we know we are between 5 and 10 what is 6^3, 7^3, 8^3, and 9^3 yeah, its 9, since 9^3 = 729 :)

25. anonymous

OK thank you

26. amistre64

the idea tho is to power the top , then root the bottom

27. amistre64

one idea, if you feel spirited: (-27)^(2/3) = y (-27)^(2/3) * (-27)^(1/3) = y(-27)^(1/3) (-27)^(2/3+1/3) = y(-27)^(1/3) -27 = y(-3) -27/(-3) = y

28. Here_to_Help15

Dividing a negative and a negative you will get a positive! IMPORTANT TO KEEP IN MIND :)

29. Here_to_Help15

Positive and negative will be NEGATIVE AND + and + will be +

30. anonymous

Yeah thanks @Here_to_Help15 very helpful

31. Here_to_Help15

:)

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