Answer:
x1 =1
x2 =2
x3 =4
Step-by-step explanation:
Given is a systems of equations in 3 variables.
No of equations given = 3
[tex]x1 + x2 + x3 = 7 ... I\\x1 - x2 + 2x3 = 7 ... II\\5x1 + x2 + x3 = 11 ... III[/tex]
subtract equation 1 form equation 3
We get
[tex]4x1=4\\x1=1[/tex]
Substitute this value in 2 and 3
[tex]x2-2x3 = -6 ... iv\\x2+x3 =6 ... v[/tex]
subtract iv from v
3x3 = 12
x3=4
Substitute in v
x2 =2
solution is
x1 =1
x2 =2
x3 =4