Question

A car tracked 649 miles at a certain speed. If the speed of had been 8 mph faster, the trip could have been made in 4 hours less time. Find the speed.

Answer 1

Answer:

Step-by-step explanation:

let s be speed and t be time taken

s*t=649

(s+8)(t-4)=649

st-4s+8t-32=649

-4s+8t-32=0

4s=8t-32

s=2t-8

2t=s+8

t=4+s/2

$s*(\frac{s}{2}+4)=649\\s^2+8s=649\\s^2+8s-649=0\\find s$