Make sure your answer is written with an inequality sign otherwise you could end up losing marks on an exam.
Examples:
1) Solve 2x + 3 < 14
Subtract 3 from both sides
2x < 11
Now divide both sides by 2
x < 5.5
This means that x can take any value below 5.5, but does not include the value 5.5. If you were asked to state the largest integer (whole number) that belongs in this set you would give the answer 5 as this is the biggest integer that is less than 5.5
2)
Sometimes you are asked to show inequalities on a number line
When dealing with inequalities remember to try to avoid multiplying or dividing by a negative number. Here's why ...
20 > 4, this inequality is true because 20 is greater than 4, now if I divide both sides by -2 the rules of equations would say my equation would be unaffected so lets try
-10 > -2, is this still true?
-10 is not greater than -2. If you must divide or multiply by a negative number when using inequalities you must remember to turn the inequality sign.
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