Dealing with the concepts of “and” and “or”, it is better that they be written in uppercase: AND and OR. This makes the ideas clearer to the students.

 

¦ax + b ¦> c Very large positive or negative x will work. This is an OR.

 

¦ax + b ¦< c If x is too large (positive or negative) it will not work. It must be in a range.

This is an AND.

 

See Absolute values.