Expert: Wei Chong - 2/6/2008

Question
[8-7y]+9=1

Answer
Hi Elizabeth,

Thanks for asking me a question.

Now,taking a look at the equation:

       [8-7y]+9 = 1

The 'objective' is to solve for y. Hence, to find y = ?, we need to remove the terms (except for 'y') on the Left Hand Side (LHS) of the equation. We can do so by:  

       [8-7y]+9 -9 = 1 -9    Remove +9 by Adding -9 both sides
       [8-7y]      = -8
       
Now, for this question, you can see that the brackets [ ] can be removed. This is because these brackets do not seem to be have any significance in the equation. So, the equation becomes:

   8 -7y      = -8
   8 -7y -8   = -8 -8    Remove 8 by adding -8 on both sides:        
     -7y      = -16      Now, remove -7 by diving -7 on both sides:
     -7y/(-7) = -16/(-7)  
       y      = 16/7     

So, we have have solved the equation with  y = 16/7.

If you need more information, you see the math video in the lesson on:

Removing brackets:
http://www.mathexpression.com/simplifying-algebraic-expressions.html

Solving linear equations:
http://www.mathexpression.com/solving-linear-equation.html