use substitution to solve the system of linear equation xy9z
use substitution to solve the system of linear equation
x+y+9z=-9
x+y+4z=-4
x-5y-2z=-22
Solution
x+y+9z=-9
x+y+4z=-4
x-5y-2z=-22
from first equation we get
x=-9-y-9z
substituting this value of x in second equation we get
-9-y-9z+y+4z=-4
z=-1
substituting this value of z in second and third equation
x+y-4=-4
x+y=0
x-5y+2=-22
x-5y=-24
So we have two equations
x+y=0 and x-5y=-24
x+y=0
x=-y
substitute this value of x in x-5y=-24
-y-5y=-24
-6y=-24
y=4
x + y +9z=-9
x +4 -9=-9
x=-4
Therefore the answer is
x=-4, y=4 and z=-1
-6y=
