Question

Give an example that shows why you need to reverse the sign when dividing or multiplying an inequality by a negative number.

Answer 1

Answer:

2 < 3 ⇒ -2 > -3

Step-by-step explanation:

∵ 2 < 3

If we divide each side by -1

∴ -2 < -3 but it's not true

∴ we must reverse the sign of inequality

∴ -2 > -3

similar:

∵ 25 > 20

If we divide each side by -5

∴ -5 > -4 it's not true

∴ we must reverse the sign of inequality

∴ -5 < -4