Answer with explanation:
Mathematically , john's statement is wrong which is:→ if one side of an inequality is 0, you don’t have to reverse the inequality symbol when you multiply or divide both sides by a negative number.
Counterexample :Consider an example
→ 4x ≥ 0, where x is a positive integer.
If we multiply or divide both sides by , -1, the inequality would result into
→ -4x ≤ 0
This transformed inequality is valid only when ,x is a Positive Integer.Here after multiplying by negative integer ,if we will not change the inequality sign, it will be an invalid Inequality.