sqrt(108)-sqrt(12)= sqrt(N)
sqrt (108) = sqrt (36 * 3) = 6sqrt(3)
sqrt (12) = sqrt (4 * 3) = 2sqrt(3)
So
sqrt (108) - sqrt (12) =
6sqrt (3) - 2sqrt(3) =
4sqrt(3) =
sqrt (16 * 3) =
sqrt (48) ......so N = 48
