Arthur D. answered 07/16/19
Forty Year Educator: Classroom, Summer School, Substitute, Tutor
distance=rate*time
d=r*t (r will represent the jogging speed, not x)
7=r*t
14=r(t+1)
from 7=rt, we get 7/r=t
substitute
14=r([7/r]+1)
14=7+r
r=14-7
r=7 mph is the jogging speed
also, t=1 hour for the 7 mile jog and it takes 2 hours for the 14 mile jog