Answer :
[tex] \: \: \: \: \: \: [/tex]
# 2a+b+c=9
answer
[tex]a = \frac{9}{2} - \frac{1}{2} b - \frac{1}{2} c[/tex]
#a+2b+c=8
answer
[tex]a = 8 - 2b - c[/tex]
#a+b+2c=11
answer
[tex]a = 11 - b - 2c[/tex]
refer to the attachment for explanation
hope it helps
