Solving linear inequalities is very similar tosolving linear equations, except for one small but important detail: you flip the inequality sign whenever you multiply or divide the inequality by a negative. The easiest way to show this is with some examples:
XXXXXXXXXXX, the solution XX:
XXXX that XXX solution to a "XXXX than, but not XXXXX to" inequality is XXXXXXX XXXX a XXXXXXXXXXX (or XXXX an open dot) at the endpoint, indicating XXXX XXX endpoint is XXX XXXXXXXX within XXX solution.
XXXXXXXX "x" in the XXXXXXXX XXXX XXX "have" XX be XX XXX XXXX. However, it is often easier to picture what the XXXXXXXX means with XXX variable on XXX left. XXX't XX afraid to rearrange things to XXXX your taste.
XXXXXXXXXXX, XXX XXXXXXXX is:
XXXX XXXX the solution XX a "less XXXX or equal XX" inequality XX XXXXXXX with a XXXXXX XXXXXXX (or else a closed XXX) at XXX XXXXXXXX, indicating XXXX the endpoint XX XXXXXXXX within XXX solution.
Graphically, the solution XX:
XXXXXXXXX &XXXX; Elizabeth Stapel 1999-2011 XXX XXXXXX XXXXXXXX
Graphically, XXX XXXXXXXX is:
The rule for example5above XXXXX XXXXX unreasonable XX students XXX XXXXX XXXX XXXX see it. But think about inequalities XXXX XXXXXXX in XXXXX, XXXXXXX of XXXXXXXXX. XXX know XXXX XXX XXXXXX four XX larger XXXX XXX XXXXXX XXX:4 > X. XXXXXXXXXXX through this XXXXXXXXXX by–X, XX get–4 &XX; –2, XXXXX the XXXXXX XXXX shows is true:
If XX hadn't flipped XXX XXXXXXXXXX, we XXXXX have XXXXX up XXXX "–X &XX; –2", XXXXX XXXXXXX isn't XXXX.