By defination ,in a neutral solution [H+] equals [OH-] .Let's call the concentration of each of these species in neutral solution x .Using equation
Kw = [H+] [OH-]
1.0 x 10-14 = x . x = x 2
x = 1.0 x 10-7 = [H+] = [ OH-]
In an acid solution [H+] is greater then 1.0 x 10-7 M , in a baisc solution [H+] is less than 1.0 x 10-7 M .
1.0 x 10-7