Question 411875
First leg speed be x mph
second leg speed = x-25 mph
...
first leg distance = 200 miles
second leg distance = 600 miles
..
total time = 18-2=16 hours

time first leg +time second eg = 16

200/x + (600/(x-25) =16
LCD = x(x-25)
multiply bth sides by x(x-25)
200(x-25)+600x=16(x(x-25))
200x-5000+600x=16x^2-400x
16x^2-1200x+5000=0
2x^2-150x+625=0
solve by using quadratic formula

a=2   , b =-150 , c =625.

b^2-4ac=17500

{{{x1=(150+sqrt(17500))/(4)}}}
speed = 70.6 mph 

{{{x2=(150-sqrt(17500))/(2a)}}}
x2= 4.4 mph This is not possible