Answer:
y=-x+5 
Explanation:
first, let's find the slope of the line (m), using the equation (y2-y1)/(x2-x1) 
here are the given points: (4,1) and (8,-3) 
label the points: 
x1=4
y1=1
x2=8
y2=-3 
now substitute into the equation
m=(-3-1)/(8-4)
m=(-4)/4
m=-1 
the slope of the line is -1. 
Now, use slope-point form, which is y-y1=m(x-x1)
substitute the numbers into the equation
y-1=-1(x-4)
do distributive prop
y-1=-x+4
add 1 to both sides
y=-x+5 
the equation of the line is y=-x+5 
hope this helps :)