Question

The augmented matrix of a consistent system of five equa- tions in seven unknowns has rank equal to three. How many parameters are needed to specify all solutions?

Answer 1

It is necessary four parameters.

Explanation:

Since the augmented matrix of the consistent system has rank equal to three then the number of free variables is (number of unknows)-rank then there are 7-3=4 free variables. This means that are necessary four parameter to specify all solutions.