## anonymous 5 years ago Use the properties of exponents to simplify the expression. Write the answer in scientific notation. (5x10^6)(6x10^-5) all divided by (4x10^8)

1. anonymous

2. anonymous

i dont understand how to do this problem

3. anonymous

first: if u have (a*x^b)(c*x^d), this equal to (a*c)x^(b+d)

4. anonymous

so, consider the top part first, change x=10,a=5,b=6,c=6,d=-5 u got me so far?

5. anonymous

even though its scientific notation i can still do it like this?

6. anonymous

scientific notation like what?

7. anonymous

well its all written in scientific notation. but if i just see it like an exponent problem i can do it like this right?

8. anonymous

yes. i used a,b,c,d,x as arbitrary. thats in general. u just have to subtitute them with numbers according to the questions.

9. anonymous

okay so i did all that. then what should i do?

10. anonymous

just to make sure, ur question is $(5\times 10^{6})(6 \times 10^{-5}) / (4 \times 10^{8})$ am i right?

11. anonymous

yes

12. anonymous

for upper part: u wil have 30*10. but 30=3*10 therefore, 30*10= 3*10*10= 3*10^2 then, use this: if u have (a*x^b)/(c*x^d), this equal to (a/c)x^(b-d) for (3*10^2)/(4*10^8)

13. anonymous

the answer should be 7.5 * 10^(-7)

14. anonymous

how -7? isnt it 2-8?

15. anonymous

because 3/4=0.75= 7.5 * 10^(-1)

16. anonymous

ohhh i get it. thank you so much!

17. anonymous

no problem. im not simply give u the answer straight away so u can learn how to do exponent problems on your own.