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 = - 83
z = 3.952
and y is found bt substituting in equation d:
-3y - 9(3.952) = 11
y = ( 11 + 9(3.952) / -3
= -15.52.
Now find x by substituting for y an z in equation a:
x - 15.52 - 3.952 = 5
x = 5 + 15.52 + 3.952
= 24.476.
