Respuesta :

i believe it is -1.
slope of a line passing though point (x1,y1) nd (x2,y2) is
(y2-y1)/(x2-x1)

we have
(1,-3) and (3,-5)
x1=1
y1=-3
x2=3
y2=-5

slope=(-5-(-3))/(3-1)=(-5+3)/(2)=-2/2=-1

slope=-1