(b) Calculate the value of y for which 2 log3 y − log3 ( y + 4 ) = 2 .
Here's my working out:
2 log3 y - log3 y - log3 4 = 2
log3 y - log3 4 = 2
log3 (y/4)=2
3^2=y/4
9=y/4
y=36
The correct answer is y=12. WHY isn't the above correct?? What have I done wrong?
THANKS