Question

solve the system of equations 2x+3y+z+11 -3x+2y+z=4 5x-4y-2z=-9 by matrix method

Answer 1

Step-by-step explanation:

From the third you get,

x=4-1

Substituting in the first, we obtain:

3(4-2y-z)+y+2z=3;

12-6y-3z+y+2z=3;

-5y-z=3-12;

-z-5y=-9;

z+5y=9;

z=9-5y

Substituting in the second one, we obtain:

2(4-2y-z)-3y-(9-5y)=-3;

8-4y-2z-3y-9+5y=-3;

8-2y-2(9-5y)-9=-3;

8-2y-18+10y-9=-3;

-19+8y=-3;

8y=19-3;

8y=16;

y=16;

8=2;

y=2

Therefore:

z=9-5y=9-5×2=9-10=-1

and

x=4-2y-z

=4-(2×2)-(-1)=4-4+1=1

So you have

So you havex=1, y=2 , z=-1