Question 1006467
Try this:


{{{-3(p-7)>21}}}
{{{-3(p-7)-21>0}}}
{{{-3p+21-21>0}}}
{{{-3p>0}}}


Critical value for p is 0.
{{{-3*0=0}}} but you want left member -3p to be GREATER THAN 0.
Negative multiplied by negative will be POSITIVE meaning greater than 0.


{{{(-3p)(-1/3)<0*(-1/3)}}}, and notice carefully the Order change;
{{{highlight(p<0)}}}