Answer:
The pair of equations which has (2,12) as its solution is,
equation B and equation C.
                             
Step-by-step explanation:
According to the question,
equation of line A is 
                             or, 
                             or, 
                             or, 3y + 4x = 24 ------------------(1)
Now, the point (2, 12) doesn't satisfy (1). Hence, (2,12) is not a solution for the line A.
Equation of line B is, 
                               or, 
                               or, 
                               or, y + 2x = 16  -----------------------------(2)
The point (2,12) is satisfied by (2). Hence, (2, 12) is a solution for line B.
Equation of line C is, 
                               or, 
                               or, y + 6 = 2x + 14
                               or. y - 2x = 8 -----------------------------------(3)
The point (2, 12) is satisfied by (3). Hence, (2 , 12) is a solution for the line C.
Equation of line D is, 
                                or, 
                                or, 7y - 140 = 27x - 189
                                or, 7y  - 27x = -49----------------------------------------(4)
The point (2, 12) is not satisfied by (4). hence, (2, 12) is not a solution of the line D
Hence, the pair of equations which has (2,12) as its solution is,
equation B and equation C.