Question

find the value of a and b if y = 1 and x = 2 is a solution of linear equation ax + by = 3 and 3a - 2b = 1?

Answer 1

ax + by = 3
a(2)+b(1)=3. {. y=1 and x=2}
2a+b=3.........(1)
3a-2b=1.........(2)

from (1) and (2)
2× {2a+b=3}
1×{3a-2b=1

On adding

4a+2b=6
3a-2b=1
______
7a. =7
a. =7/7
a. =1

put the value of a in (1)
2×1+b=3
2+b =3
b =3-2
b=1

a=1
b=1