Answer:
4 parameters are necessary to specify all solutions and correspond to the number of free variables of the system.
Step-by-step explanation:
Remember that the number of free variables of a system is equal to m-rank(A) where m is the number of unknowns variables and A is the matrix of the system.
Since the system is consistent and the rank of the matrix is 3 then echelon form of the augmented matrix has two rows of zeros.
Then m-rank(A)=7-3=4.
The answer is 76 your welcome
because there are 12 in one layer and there are 3 layers
