If the square root of three times a number is 15 how do you find the number?

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Answer 1 · 2015-09-16T22:23:42

If #sqrt(3n) =15#
then #n = 75#

Method 1
#sqrt(3n) =sqrt(3)*sqrt(n)#

#sqrt(3)*sqrt(n) = 15#

#sqrt(n) = 15/sqrt(3)#

#=(15sqrt(3))/3 = 5sqrt(3)#

#n = (5sqrt(3))^2#

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

#=25*3#

#=75#

Method 2
If #sqrt(3n) =15#

then

#3n = 15^2 = 225#

#n=75#