Question 612588
Let Phil's apeed be x ft/m
Heim's speed = x+2 ft/m

distance = 450 ft
time = distance/speed
time taken by Phil - time taken by Heim = 2.5
450/x  - 450/(x+2)= 2.5
LCD = x(x+2)

multiply equation by LCD
450(x+2)-450x= 2.5x(x+2)
450x+900-450x=2.5x^2+5x

2.5x^2+5x-900=0
/2.5
x^2+2x-440=0
x^2+22x-20x-440=0
x(x+22)-20(x+22)=0
(x+22)(x-20)=0
x= 20 OR -22 
speed cannot be negative. so phil's speed = 20ft/m