5x + 9 = 5 + 3x

5x – 3x = 5 - 9

2x = -4

x = -2

L.H.S: 5(-2) + 9 = -1

R.H.S: = 5 + 3(-2) = - 1

Since L.H.S. = R.H.S

Hence, the solution is correct.