Question 998641
Distance = 380 miles

return speed =x

going speed = x+25

Time forward + time return = 13

t=d/r

{{{390/x + 390/x+25) =13}}}

<ultiply equation by x(x+25)

390(x+25)+390x = x(x+25)*13

390x+9750 +390x=(x^2+25x)*13

780x +9750 = 13x^2+325x

13x^2-780x+325x-9750=0

13x^2-455x-9750=0

solve to get return speed = 50 mph