Question

For $k\ne 0$, if $x>y$, then the inequality which is not always correct is

• A. $x+k>y+k$
• B. $x-k>y-k$
• C. $kx>ky$
• D. $\frac{x}{k^2}>\frac{y}{k^2}$

Answer 1

The correct option is C $kx>ky$

$x>y$
$\Rightarrow kx>ky$ if $k>0$
$x>y$
$\Rightarrow kx<ky$ if $k<0$
so only incorrect option is option $\left(c\right)$