SOLUTION: You and your friend part at an intersection. Your friend drives away north at a constant speed. You linger at the intersection for an hour, and then drive off due east at a speed t
Algebra.Com
Question 1174517: You and your friend part at an intersection. Your friend drives away north at a constant speed. You linger at the intersection for an hour, and then drive off due east at a speed that is 11 miles per hour faster than your friend's speed. 2 hours after your friend's departure the distance between the two of you is 106 miles. Your friend is traveling at a speed of miles per hours.
Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website!
You and your friend part at an intersection.
Your friend drives away north at a constant speed.
You linger at the intersection for an hour, and then drive off due east at a speed that is 11 miles per hour faster than your friend's speed.
2 hours after your friend's departure the distance between the two of you is 106 miles.
Your friend is traveling at a speed of miles per hours.
:
let s = friends speed mph
since he travels 2 hrs
2s = distance friend is from intersection
:
Your travel time is only 1 hr since you started 1 hr later,
traveling 11 mph faster, therefore
1(s+11) = your travel distance
:
pythag: a^2 + b^2 = c^2, where
a = 2s
b = (s+11)
c = 106
:
(2s)^2 + (s+11)^2 = 106^2
FOIL(s+11)(s+11)
4s^2 + (s^2 + 22s + 121) = 11236
4s^2 + s^2 + 22s + 121 - 11236 = 0
Combine like terms, a quadratic equation
5s^2 + 22s - 11115 = 0
Use the quadratic formula: a=5; b=22, c=-11115
I got a positive solution of
s = 45 mph is your friends speed
:
:
Check on your calc
= 106
RELATED QUESTIONS
You and your friend part at an intersection. You drive off north at a constant speed, and (answered by mananth)
You and your friend part at an intersection. You drive off north at a constant speed, and (answered by ankor@dixie-net.com)
You and your friend part at an intersection. You drive off north at 50 mph, and your... (answered by solver91311)
You and your friend part at an intersection. You drive off north at 50 mph, and your... (answered by xdragonfight)
You and your friend part at an intersection. You travel north at a constant speed and... (answered by lwsshak3)
You forgot your homework assignment in Dallas. A friend agreed to meet you part way and... (answered by askmemath)
At 1pm your friend leaves for college traveling on the interstate at a constant speed of... (answered by ankor@dixie-net.com)
at 1pm your friend leaves for college traveling on the interstate at a constant speed of... (answered by ankor@dixie-net.com)
you and a friend take turns driving on a 450 mile trip. Your friend drives for 3.5 hours (answered by graphmatics)