## anonymous one year ago I need help with some algebra homework. It is simplifying expressions with exponents. Please help!!

1. anonymous

$-2n ^{4} (12n ^{-7})$

2. anonymous

@Hero

3. anonymous

@pooja195

4. anonymous

@dan815

5. anonymous

@amistre64

6. anonymous

Multiply the coefficients and add the exponents $-2n^4(12n^-7)=(-2 \times 12)n^{4+(-7)}$

7. anonymous

but i need to simplify it. example: $-3n ^{2} (8n ^{-5}) =\frac{ -24 }{ n ^{3} }$

8. anonymous

I'm having trouble understanding the whole steps...

9. anonymous

-24/n³ is simplifed

10. anonymous

To multiply expressions when the bases are the same, add the exponents and multiply the coefficients $(-3n^2)(8n^{-5})=(-3 \times 8)n^{2+(-5)}=-24n^{-3}$ For negative exponents, if you take the reciprocal of the base, you can make the exponent positive Rule: $x^{-m}=\left( \frac{ 1 }{ x } \right)^m$ That's why the -3 became 3 and the n moved to the denominator $-24n^{-3}=-24\left( \frac{ 1 }{ n } \right)^3=\frac{ -24 }{ n^3 }$

11. anonymous

That was exactly what my teacher was trying to show us. It's just I was having trouble. Thanks for the help! :)

12. anonymous

you're welcome