How do you evaluate #3\sqrt { 45} - 2\sqrt { 12} - 2\sqrt { 27}#?

1 Answer
May 8, 2017

I got: #9sqrt(5)-10sqrt(3)#

Explanation:

We can write our expression changing a bit the apparence of the quantities inside the square roots mas:
#3sqrt(5*9)-2sqrt(3*4)-2sqrt(3*9)=#
we can write:

#=3sqrt(5)sqrt(9)-2sqrt(3)sqrt(4)-2sqrt(3)sqrt(9)=#

#=3*3sqrt(5)-2*2sqrt(3)-2*3sqrt(3)=#

#=9sqrt(5)-4sqrt(3)-6sqrt(3)=9sqrt(5)-10sqrt(3)#