## anonymous 5 years ago Hello All! Would anyone mind helping me with rationalizing denominators?

1. anonymous

sure :)

2. anonymous

Is there a specific formula for this?

3. anonymous

well do u have an example problem? it would b easier to explain with one

4. anonymous

the first one is $7/\sqrt{5}$

5. anonymous

the slash line is equivalent to a fraction, FYI :)

6. anonymous

....

7. anonymous

if you don't know it, that is fine.

8. anonymous

ok so what you do is you multiply both the numerator and the denominator by the square root of 5. so you have 7*square root of 5 __________________ square root of 5* square root of 5. this gives you 7square root of 5 ________________ 5

9. anonymous

does this help? sorry i dont know how to do the square root sign on here....

10. anonymous

yes- you basically simplify the it to be 7$\sqrt{5}/5$

11. anonymous

yep :) if u think i helped, then click the good answer button :)

12. anonymous

13. anonymous

hello?

14. anonymous

$\frac{8}{3+\sqrt{7}}=12-4 \sqrt{7}$