Answer:x = 24.48, y = -15.52, z = 3.95 to the nearest hundredth.Step-by-step explanation: x+y-z=5 (a) -x-4y-8z=6 (b)3x+5y-4z=-20 (c)Adding equations a and b:-3y - 9z = 11 (d)Now multiply equation b by 3:-3x - 12y - 24z = 18 (e)Adding c and e:-7y - 28z = -2 (f) Multiply by 3 to give (g)-3y - 9z = 11 (b) Multiply by -7 to give (h)-21y - 84z = -6 (g)21y + 63z = -77 (h) Adding g and h:-21z = - 83z = 3.952and y is found bt substituting in equation d:-3y - 9(3.952) = 11y = ( 11 + 9(3.952) / -3= -15.52.Now find x by substituting for y an z in equation a:x - 15.52 - 3.952 = 5x = 5 + 15.52 + 3.952= 24.476.