Respuesta :

pure algebra:
4x - c= k 
add + c to both sides:
4x - c (+c) = k (+c)
4x = k +c
divide both sides by 4:
4x/4 = k+c/4
x = k+c /4

so answer is b)


4x - c=k for x
add c on both sides
4x - c + c = k + c
simplify
4x = k + c
Divide both sides by 4
4x / 4 = (k + c)/4
simplify
x  = (k + c)/4

answer
x  = (k + c)/4