5. Suppose that x1 =3, x2 =0, x3 =−1, x4 =5 is a solution of a nonhomogeneous linear system Ax=b and that the solution set of the homogeneous system Ax=0 is given by the formulas

x1 =5r −2s, x2 =s, x3 =s+t, x4 =t

(a) Find a vector form of the general solution of Ax=0.

(b) Find a vector form of the general solution of Ax=b.

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