Looking at the given diagram,
HI + JI = JH
Given the HI = 3x - 5
JI = x - 1
HJ = 7x - 27
Therefore,
3x - 5 + x - 1 = 7x - 27
3x + x - 7x = - 27 + 5 + 1
- 3x = - 21
Diving bith sides - 3, it becomes
- 3x/3 = - 21/- 3
The negative signs nullify each other
x = 7