This document discusses solving equations and identities in mathematics. It provides an example of solving the equation 6x + 2x + 4 = 3x + 3 – 5x – 9 and obtaining the solution x = -1. It also gives an example of solving the identity 3x – 4 + 2x – 3 = 4x – 6 + x – 1 and obtaining the solution 0x = 0. Finally, it states that the equation - 4x – 1 + 2x + 5 = 5x + 6 – 7x + 4 is incompatible since solving it results in 0x = 6, which has no solution.

1. Matemàtiques 2 ESO
IDENTITATS I
EQUACIONS INCOMPATIBLES

2. UNA EQUACIÓ
6x + 2x + 4 = 3x + 3 – 5x – 9
Es resol:
6x + 2x + 4 = 3x + 3 – 5x – 9
6x + 2x – 3x + 5x = - 4 + 3 – 9
10 x = - 10
X = - 1

3. Una identitat
3x – 4 + 2x – 3 = 4x – 6 + x – 1
Es resol:
3x + 2x – 4x – x = 4 + 3 – 6 – 1
0x = 0

4. Una equació incompatible
- 4x – 1 + 2x + 5 = 5x + 6 – 7x + 4
Es resol:
- 4x + 2x – 5x + 7x = 1 – 5 + 6 + 4
0x = 6