Answer:
The correct options are C and D
Only multiplication by a negative number and division by a negative number changes the inequality sign
Explanation:
Consider the inequality:
[tex]5>2[/tex]
This is clearly true that 5 is greater than 2
adding a positive number on both sides would not change the inequality sign, because:
[tex]\begin{gathered} 5+1>2+1 \\ 6>3 \end{gathered}[/tex]
6 is truly greater than 3
Same thing goes with subtracting a negative number, it won't change the inequality sign.
Multiplying by a negative number though,
[tex]\begin{gathered} 5\times-2>2\times-2 \\ -10>-4 \end{gathered}[/tex]
This is NOT TRUE, because -10 is less than -4, and hence, we change the inequality sign as
[tex]-10<-4[/tex]
Division by a negative number also changes the inequality sign.
In conclusion, only multtplication by a negative number and division by a negative number changes the inequality sign.