Answer:
You have to eliminate one of the variables when the equations are added.
A) x + 2y + z = 10
B) 2x -y +3z = -5
C) 2x -3y -5z = 27
We mulutiply A) by 2 then add it to B and C
A) 2x + 4y + 2z = 20 and the sum =
6x = 42 Luckily, the "y" and "z" variables cancel out and we find:
x = 7
Then we use x =7 in calcucating equation A) and B)
A) 2y + z = 3
B) -y + 3z = -19
THEN solve for y and z by eliminating variables.
Explanation: