Which is the equation of the line passing through (0 4) and (8 0)

First we find slope.
So the slope would be 0-4/8-0 which is -4/8 and reduces to -1/2.
Y=(-1/2)x+b
Then plug in one set of points to find b.
4=(-1/2)(0)+b
4=b
The equation would be
y=(-1/2)x+4