Answer:
b both pairs of opposite sides are parallel
Equation for slope=1/3 and y-intercept=-1 is:
y = mx + b
where m is slope and b is y-intercept.
So, equation becomes
y = -1x + 1/3
Now put different values of x in the equation to get corresponding value of y.
x y
0 1/3
1 -2/3
2 -5/3
3 -8/3
-1 4/3
-2 7/3
-3 10/3
So it means every 30 minutes he runs 6 miles