How do you solve for x in the equation bx - c = a

Do x divided by b on both sides and then add a on both sides. :)

You have to get x on one side, so you add c to both sides, canceling it from the left side and leaving a+c on the right. then you divide both sides by b to cancel it out, leaving just x on the left side and a+c/b on the right

Best answer that i found on yahoo ok   set :   x= length of 2nd piece in cm  x- 3= length of 1st piece in cm  x-4= length of 3rd piece in cm  then since you know they all came from the 20 cm ribbon you add them together and set them equal to 20x+ x-3 +x-4 = 20  3x - 7= 20  3x= 27  x= 9  the shortest piece is the third piece which is x- 4  x-4  9-4 = 5  the length of the smallest piece is 5 cm.  the other lengths are  9 cm  6 cm