Solving Simple Equations

Date: 02/23/98 at 16:17:26
From: Elizabeth Parker
Subject: Solving simple equations

I have been in Algebra for 3 months now and we are in factoring (the 
very beginning of it). I understand all this, but I can't solve 
equations like 3(30+s) = 4(s+19) and others following the same form. 
If I could get all the help I can, I would really appreciate it!

Thank you -

Elizabeth Parker

Date: 02/24/98 at 14:01:12
From: Doctor Johnny
Subject: Re: Solving simple equations

Elizabeth,

Hello there.  I hope that I can help you work out this problem and any 
other ones that you encounter in the future.

One of the first things you must consider in problems like these is, 
"How do I get rid of the parentheses?"  I hope you remember the 
distributive property.  If you've forgotten, here is a small reminder.  
The distributive property is where you distribute (give) the number 
outside the parentheses to the numbers on the inside of the 
parentheses through multiplication.  

For example:     2(3x+5) = 2(3x) + 2(5) = 6x + 10

In your problem: 3(30+s) = 4(s+19)
                 90+3s is the result of 3(30+s)
                 4s+76 is the result of 4(s+19)

Once we have used the distributive property, our equation becomes:

     90+3s = 4s+76

and you must consider getting all the variables on one side and all of 
the constants on the other. It doesn't matter which variable you move, 
but one must be moved so that all of the variables are on the same 
side. Once the variables are one one side and the constants are on the 
other, you might need to finish solving the equation the way you  
normally would.

I am now going to turn the problem back over to you. See if you can 
get the answer 14. I hope that this brief explanation will help you 
solve other equations in the future. Good luck, and write us back 
if you still don't understand.

-Doctor Johnny,  The Math Forum
Check out our web site http://mathforum.org/dr.math/