That's OK, but you have not said which variable you want to solve it for.
To solve for 'x':
c + ax = dx
Subtract c from each side: ax = dx - c
Subtract dx from each side: ax - dx = -c
Factor the left side: x (a - d) = -c
Divide each side by (a - d) : x = -c / (a - d) or x = c / (d - a) .
To solve for 'c':
c + ax = dx
Subtract ax from each side and factor: c = x (d - a)
To solve for 'd':
c + ax = dx
Divide each side by 'x': d = c/x + a .
To solve for 'a':
c + ax = dx
Subtract 'c' from each side: ax = dx - c
Divide each side by 'x': a = d - c/x .
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