Question 757029
Treating a, b, and c as numbers while they are not shown by the digits means you use all the rules that you know or have studied but do not perform any computations between any of a, b, or c.  


a+bx=c
Use additive inverse of a:
{{{a+-a+bx=c+(-a)}}}
{{{0+bx=c+(-a)}}}
Use the multiplicative inverse of b:
{{{(bx)(1/b)=(c+(-a))(1/b)}}}
{{{b(1/b)x=(c+(-a))(1/b)}}}
{{{1*x=(c+(-a))(1/b)}}}
A little more simplifying without further explanation:
{{{x=(c-a)/b}}}