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11 votes
Solve the system.
-5x + 7y +z = 16
x + y - 4z = -6
-2x – 3y – z= -8

User Wohops
by
7.6k points

1 Answer

11 votes

Given :

System of equations :

-5x + 7y + z = 16 ...1)

x + y - 4z = -6 ...2)

-2x -3y -z = -8 ...3)

To Find :

The solution of given system.

Solution :

Putting value of x from equation 2) in equation 1) and 3), we get :

5( -6 + 4z - y ) + 7y + z = 16

21z + 2y = 46 ...4)

-2( -6 + 4z - y ) - 3y - z = -8

12 - 8z + 2y - 3y -z = -8

-9z - y = -20 ...5)

Multiplying equation 5) by 2 and adding equation 4), we get :

3z = 6

z = 2

y = 20 - 18 = 2

Putting value of z and y in equation 2), we get :

x + 2 - 8 = -8

x = -2

Therefore, the solution of the system is ( -2, 2, 2).

User Abhinav Goyal
by
7.2k points