How do you evaluate #sqrt5-3sqrt5#?

1 Answer
Apr 9, 2018

#-2sqrt5#

Explanation:

First of all:

#sqrt5# is the same as saying #1sqrt5# since anything times #1# is itself.

So we can change the equation a little:

#1 sqrt5 - 3sqrt5#

Since these are being multiplied by the same square root, we can combine the numbers outside the radicals (#sqrt# signs) by subtracting # 1 - 3# and leaving the #sqrt5# in the answer:

#1sqrt5 - 3 sqrt5 = -2sqrt5#