SOLUTION: Can someone please help, my son has come to me for help with his Algebra HW. I have not been in school for over 20 years & cannot remember ANY of it. Here is the problem, if you ca

Algebra ->  Inequalities -> SOLUTION: Can someone please help, my son has come to me for help with his Algebra HW. I have not been in school for over 20 years & cannot remember ANY of it. Here is the problem, if you ca      Log On


   



Question 671969: Can someone please help, my son has come to me for help with his Algebra HW. I have not been in school for over 20 years & cannot remember ANY of it. Here is the problem, if you can show me each step I can maybe be of some help to him:
5n+3-4n<-5-3n

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
First, you have to recognize what it is
It's an INequality.
There are 4 types of inequalities
> means greater than
< means less than
>= means greater than or equal to
<= means less than or equal to
----------------------------
The plain old = means equal to
Your inequality is
+5n+%2B+3+-+4n+%3C+-5+-+3n+
This says that the left side is less than the
right side. There is 1 unknown, n, in this inequality
----------------------------
The basic rule with inequalities is the same as
when you just have an = sign.
Whatever you do to one side, you must do the exact
same thing to the other side
------------------------
First, I'm going to subtract 3 from both sides
+5n+%2B+3+-+3+%3C+-5+-3+-+3n+
+5n+%3C+-8+-+3n+
Now I will add +3n+ to both sides
+5n+%2B+3n+%3C+-8+-+3n+%2B+3n+
+8n+%3C+-8+
Divide both sides by +8+
+%288%2F8%29%2An+%3C+%28-8%2F8%29+
+n+%3C+-1+
-----------
Notice that the < sign never changed, and
it usually does not.
-----------
There is very simple way to check the work.
I am saying that n is less than -1,
so I will say that +n+=+-1.01+ which is
slightly less than +-1+
+5n+%2B+3+-+4n+%3C+-5+-+3n+
+5%2A%28-1.01%29+%2B+3+-+4%2A%28-1.01%29+%3C+-5+-+3%2A%28-1.01%29+
+-5.05+%2B+3+%2B+4.04+%3C+-5+%2B+3.03+
( note that minus x minus = plus )
+%2B+3+-+1.01+%3C+-5+%2B+3.03+
+-1.99+%3C+-1.97+
This is true, so I think my solution is correct
--------------
Hope this helps