How do you simplify #sqrt20-sqrt5#?

2 Answers
Reactionary Green Negroid
May 31, 2018

#sqrt(5)#

Explanation:

Since 20 is divisible by 4, which is a perfect square, #sqrt(20)# which is the same as #sqrt((4*5))# can be written as 2#sqrt(5)# by taking the 4 out of the radical and square rooting it. Hence, we can now derive:

2#sqrt(5)# - #sqrt(5)# = #sqrt(5)#

Therefore, the answer is #sqrt(5)# which is approximately 2.236.

sjc
May 31, 2018

#sqrt5#

Explanation:

#sqrt20-sqrt5#

#=sqrt(4xx5)-sqrt5#

#=sqrt4sqrt5-sqrt5#

#=2sqrt5-sqrt5#

#=sqrt5#

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