Given data
A. 9x - 3x - 4 = 6x - 4
B. 12x - 4
C. 5x + x - 4 = 6x - 4
For x = 0,
Each expression is equal to -4.
The three expressions are equivalent when x = 0, but not equivalent for any other values of x.
Brianna error
Expreesion 12x - 4 is not equivalent to expressions 9x - 3x - 4 and 5x + x - 4 for other values of x.
Hence, only expressions
9x - 3x - 4 is equivalent to 6x - 4
Hence only expressions A and C are equivalent.