56x1 x2+3x3 8. a) Show that this constraint is equivalent to the constraints 6x1 x2+3x3 + x4 = 8, 0x4 3. b) Indicate how the general interval linear program n Maximize z=cjxj, subject to: j=1 bajxjbi (i = 1, 2,...,m), j=1 x; 0 (j = 1, 2,...,n), can be formulated as a bounded-variable linear program with m equality constraints.