Question 369480
Use the formula for slope,
{{{m=(y[2]-y[1])/(x[2]-x[1])}}}
{{{(12-(-10))/(r-(-2))=-11}}}
{{{(12+10)/(r+2)=-11}}}
{{{-11(r+2)=22}}}
{{{r+2=-2}}}
{{{highlight(r=-4)}}}