7(x-2) = 9x - 2
open the parenthesis
7x - 14 = 9x - 2
collect like term
9x - 7x = -14 + 2
2x = -12
Divide both-side of the equation by 2
x = -6
It has exactly one solution
9x+3 =3(3x+1)
9x + 3 = 9x + 3
Since the left-hand side is exactly the same as the right hand side, then it has infinitely many solutions
3x + 2 = 7(x-2)
open the parenthesis
3x + 2 = 7x - 14
collect like term
7x -3x = 2 + 14
4x = 16
Divide both-side by 4
x = 4
It has exactly one solution