3 log 2x_1 _ 3 log x_3 = 3 log 7

3 log nya di coret jadi dapat persamaan
2x-1-x-3=7
x-4=7
x=7+4
x=11

3 log 2x -1 - 3 log x - 3 = 3 log 7
3 log (2x -1 / x -3 ) = 3 log 7
2x -1 = 7(x-3)
2x-1 = 7x -21
- 5x = - 20
x = 4