Answer:
Option B is correct.
Step-by-step explanation:
4x+3y-z= -6 eq(1)
6x-y+3z= 12 eq(2)
8x+2y+4z=6 eq(3)
We need to solve these equations and find the value of x, y and z.
Multiply equation 2 with 3 and then add equation 1 and 2
18x -3y +9z = 36
4x +3y -z = -6
_____________
22x + 8z = 30 eq(3)
Multiply equation 2 with 2 and add with equation 3
12x -2y + 6z = 24
8x +2y +4z = 6
____________
20x + 10 z = 30 eq(4)
Multiply equation 3 with 10 and equation 4 with 8 and then subtract
220x + 80z = 300
160x + 80z = 240
- - -
_________________
60x = 60
x= 60/60
x= 1
Putting value of x in equation 3
22x + 8z = 30
22(1) + 8z = 30
8z = 30 - 22
8z = 8
z = 8/8
z=1
Putting value of x and z in equation 1
4(1)+3y-(1)=-6
4 + 3y -1 = -6
3 + 3y = -6
3y = -6 -3
3y = -9
y = -3
so, Option B x=1, y=3 and z=1 is correct
