8. (a) For A in Exercise 6, part (b) and b = [30, 30, 20], if Ax = b has the given solution x' [10, 10, 0, 0], find the family of all solutions to Ax = b. (b) Find a solution to Ax = b in part (a) with x, = 5.6. For the following matrices, describe the set of vectors in the null space. 341 2150 \"\"241 091243 1131