Question 356302
Use the distance formula,
{{{D=sqrt((x[2]-x[1])^2+(y[2]-y[1])^2)}}}
{{{D=sqrt((5-(-1))^2+(5-(-3))^2)}}}
{{{D=sqrt((5+1)^2+(5+3)^2)}}}
{{{D=sqrt((6)^2+(8)^2)}}}
Finish the calculation to get the distance.
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Now find the slope using the two points.
{{{m=(y[2]-y[1])/(x[2]-x[1])=8/6=4/3}}}
Perpendicular lines have slopes that are negative reciprocals.
{{{m[1]*m[2]=-1}}}
{{{(4/3)*m2=-1}}}
{{{m[2]=-3/4}}}
Now you have the slope of the perpendicular bisector, you just need the midpoint of the first line. 
Use the midpoint formula,
{{{x[m]=(x[1]+x[2])/2=(-1+5)/2=4/2=2}}}
{{{y[m]=(y[1]+y[2])/2=(-3+5)/2=2/2=1}}}
Now you have the slope and a point for the perpendicular bisector, use the point slope form of a line,
{{{y-y[p]=m(x-x[p])}}}
{{{y-1=-(3/4)(x-2)}}}
{{{y-1=-(3/4)x+3/2}}}
{{{y=-(3/4)x+3/2+2/2}}}
{{{highlight(y=-(4/3)x+5/2)}}}
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{{{drawing(300,300,-8,8,-8,8,grid(1),line(-1,-3,5,5),locate(5.2,6,B),locate(-1.5,-3,A),circle(2,1,0.2),circle(-1,-3,0.2),circle(5,5,0.2),graph(300,300,-8,8,-8,8,-(3/4)x+5/2))}}}