Which equation represents the graph?

slope=3

y_intercept =_2

y=mx+b

y=3×_2

is the equation of the graph.

for finding the midpoint of any given 2 pair of points simply add the respective x coordinates with other x coordinate and the y coordinate with other y coordinate and divide them by 2

in your question it will be :

(3+1)/2 for the x coordinate of mid point i.e 2

[8+(-4)]/2 for the y coordinate of midpoint i.e 2

so coordinates of mid point of points (3,8) and (1,-4) will be (2,2)

rounding to the nearest thousandth would be 452,000