Question

2x+3y+z=7 x-3=2y-2z 3x-y-4+z=0

Answer 1

2x+3y+z =7 ------(1)

x-2y+2z=3------(2)

3x-y+z=4------(3)

a) subtract (1) from (3)
x-4y = -3----(4)
b) subtract (2) from 2*(3)

5x= 5
x= 5/5
x=1
substitute x=1 in (4)
x-4y=-3
1-4y = -3
-4y =-3-1
-4y =-4
y = -4/-4
y=1
substitute x and y values in (3)
3x-y+z=4

3*1-1+z =4
3-1+z =4
2+z=4
z=4-2
z= 2
therefore
x=1,y=1,z=2