Question

X-y+z=4
X-2y-2z=9
2x+y+3z=1 solve by elimination method

Answer 1

x- y+ z=4............eq1

x-2y-2z=9..........eq2

- + + -

.........…........

y+ 3z = -5 ........eq4

2x+ y+ 3z=1 ........eq3

2x-2y+2z=8..........eq1*2

- + - -

......................

3y+z=-7........eq5

y+3z=-5........eq4

9y+3z=-21.......eq5*3

- - +

..............

-8y=16

y=-2

putting in eq4

-2+3z=-5

z=-1

putting in eq1

x-(-2)+(-1)=4

x=3