Scribe Post #5
Learning Target:
Solve inequalities using using physical models, paper and pencil, tables, and graphs.
How it Works, What it is:
Here is an example problem: x-7 < 3 This may look confusing, but the answer lies in finding all the possible numbers that can represent the variable x. Since < means that the right side of the equation is greater, we know that x has to be less than 10 because 9-7=2, 8-7=1, and so on. If you do 10-7, 3 still wouldn't be greater, just equal. The equation can be written like this:
x - 7 <3
bring down the x +7 +7 add 7 to each number
_________
0 10
x < 10
You can also do this on number lines, which makes things a heck of a lot easier. For example, x<4 has to be any number less than 4. This number line shows this by putting an arrow leading left from four to up to negative infinity. This graph shows that any number less than 4 could represent x.
Here is another example: -2 < x ≤ 4
(Note that this is a different level. Click here for more info on that kind of inequality, and the regular kind.)
If you really want to search this topic more, then this page is for you!
You've got it now!
Posted by: rutterj in: My entries
Modified on April 25, 2007 at 2:03 AM