a . 5x + 10 = 5x + 10 ( ecuatie de tipul stanga identica dreapta )
⇒ ecuatie cu o INFINITATE de solutii x ∈ R
b. -7x - 21 = - 7x - 21 solutia x ∈ R
c. - 4x + 3 = - 4x + 5 stanga ≠ dreapta
ecuatia nu are solutie x ∈ Ф
d. 8x + 2 = 8 x + 2 x ∈ R
e. 7x = 2x - 30 ; 5x = - 30 solutie UNICA x = - 6
f. -9x - 45 = - 7x - 49 ; - 9x + 7x = - 49 + 45
- 2x = - 4 , solutie UNICA x = 2