Question 37237
720/(x+30)+720/(x-30)=10 or [720(x-30)+720(x+20)]/x+30)(x-30)=10 or

(720x-21600+720x+216000)/(x~2-900)=10 or 10x~2-9000=1440x or

10x~2-1440x-9000 or x~2-144x-900 or (x-150)(x+6)=0 or x=150mph