## anonymous 5 years ago How do i go about this rational expression problem? Bob and Jack enter a 1000-km bicycle race. Bob cycles 4 km/h faster than Jack, but his bicycle gets a flat tire, which takes 30 minutes to repair. If the both of them finish the race in a tie, then how fast was each boy cycling? Give your answer in one decimal place.

1. anonymous

assume the velocity for jack=v then velocity for bob=v+4 total time for bob=$[1000/(4+v)]+0.5$ it has to equal to time for jack=$1000/v$ after solving the 2 equition, we got v=87.465, and v+4=91.465 for only one decimal v=jack=87.5 km/h v+4=bob=91.5 km/h

2. anonymous

How would i go about actually solving that equation though?

3. anonymous

$[1000/(4+v)]+0.5=1000/v$ $(1000+2+0.5v)/(4+v)=1000/v$ times the button to the other side $1002v+0.5v^2=4000+1000v$$0.5v^2+2v-4000=0$ use the formula v= $[-b+\sqrt{b^2-4ac}]/2a$

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