Answer:
x = 3, y = 2 and z = 1.
Explanation:
4x+y−z=13
3x+5y+2z=21
2x+y+6z=14
Subtract the third equation from the first:
2x - 7z = -1 ........... (A)
Multiply the first equation by - 5:
-20x - 5y + 5z = -65
Now add the above to equation 2:
-17x + 7z = -44 ...... (B)
Now add (A) and (B)
-15x = -45
So:
x = 3.
Substitute x = 3 in equation A:
2(3) - 7z = -1
-7z = -7
z = 1.
Finally substitute these values of x and z in the first equation:
4x+y−z=13
4(3) +y - 1 = 13
y = 13 + 1 - 12
y = 2.
Checking these results in equation 3:
2x+y+6z=14:-
2(3) + 2 + 6(1) = 6 + 2 + 6 = 14
- checks out.