Expert: Lynn Houston - 10/17/2009

Question
We need help with equations using letters. 50 =x/ 10. We know how to do + and - but how do you do the equations when division or multiplication is used, also fractions.

Answer
The secret to any of these is that you have to "undo" everything that is done to the variable that you are solving for.  So, in this case, you are dividing x by 10, so you have to multiply both sides of the equation by 10.  that gives you, 500 = x.

If it were 50 = 10x, then, since you're multiplying x by 10, you would have to divide both sides by 10 to get x = 5.

Make sense?  The same way that subtraction "undoes" addition and vice versa, multiplication "undoes" division and vice versa.