Respuesta :

9x - 2x + 3 = 3x + 4x + 3
Subtract 3 from both sides:
9x - 2x + 3 - 3 = 3x + 4x + 3 - 3 
Which then:
= 9x - 2x = 3x + 4x
Add similar elements: 9x - 2x = 7x
7x = 3x + 4x
Add similar elements: 3x + 4x = 7x
7x = 7x
The, subtract 7x from both sides
7x - 7x = 7x - 7x 
Simplify,
0 = 0
So, both sides are equal.