How do you rationalize the dominator and simplify for the square root of 35 over the square root of 55?

1 Answer
Nov 5, 2015

sqrt(77)/11

Explanation:

Your expression is sqrt(35)/sqrt(55). Since you can always mutiply an expression by 1 without changing its value, and you can see 1 as any number divided by itself, we have

sqrt(35)/sqrt(55)=sqrt(35)/sqrt(55)*1 = sqrt(35)/sqrt(55)*sqrt(55)/sqrt(55)

Doing the multiplications (remember that sqrt(a)*sqrt(b)=sqrt(a*b)), we have

sqrt(35*55)/sqrt(55^2)

And of course sqrt(a^2)=a (if a is positive), so we have

sqrt(1925)/55.

Finally, we can factor 1925 with prime numbers, and we have

1925 = 5^2*7*11, and so sqrt(1925)=sqrt(5^2*7*11)=5sqrt(7*11), and 5 and 55 cancel out.