if x=-2 , y=6 is solution of equation 3ax+2by=c then find the value of b from 2(a-1)+2(3b-4)=4
this is solving simaltaneous equations. the second equation is in variable a,b format.
in the first equation insert the values of x and y
3ax + 2by = c
3a(-2) + 2b(6) = c
1). -6a + 12b = c
2). 2(a-1)+2(3b-4)=4
2). 2a - 2 + 6b - 8 = 4
2). 2a + 6b = 14
final vedrsions of the original equations:
1). -6a + 12b = c
2). 2a + 6b = 14 multiply this by 3 to add the equations and eliminate the variable a
3*2). 6a + 18b = 42
1). -6a + 12b = c
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30b = 42 + c
b = (42 + c) / 30