jika log (x-5) = log x - log 5, maka

sifat logaritma

log(a/b) = log a - log  b

jawab:

log (x-5) = log x - log5

log (x-5) = log(x/5)

x-5 = x/5

5(x-5)= x

5x-25= x

5x = x+25

5x-x=25

4x=25

x=25/4

x= 6,25