## TheEdwardsFamily one year ago Help.

1. anonymous

Questions?

2. TheEdwardsFamily

one sec

3. TheEdwardsFamily

here it is. @kieran01pd2016

4. TheEdwardsFamily

5. TheEdwardsFamily

@Michele_Laino @triciaal

6. welshfella

use the rule of indices (x^a)^b = x^(ab)

7. anonymous

Bascially, when you put an exponent on an exponent they multiply. So if you have (2^2)^3, it is the same as writing 2^6. Therefore, in this case, what times -5 would give you -15

8. welshfella

in your problem the exponent multiplies the -5 to get -15

9. Michele_Laino

If we apply the rule of power of power, we can write this: $\Large {\left( {{2^{ - 5}}} \right)^N} = {2^{ - 5 \cdot N}} = {2^{ - 15}}$ and then we have to solve this equation: $\Large - 5 \cdot N = - 15$ please solve that equation for N

10. TheEdwardsFamily

so...what you're saying is that 3 will be the answer? (accordinng to my work)

11. Michele_Laino

correct! it is N=3

12. TheEdwardsFamily

Whoop! thanks