SOLUTION: Solve Problems Using Linear Systems 6.Kareem took 5h to drive 470 km from Sudbury to Brantford.For part of the trip, he drove at 100 km\h. For the rest of the trip, he drove at 90

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Question 185635: Solve Problems Using Linear Systems
6.Kareem took 5h to drive 470 km from Sudbury to Brantford.For part of the trip, he drove at 100 km\h. For the rest of the trip, he drove at 90 km\h. How far did he drive at each speed?
Can you please help me solve this problem.i dont understand. thank you
Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website!
6.Kareem took 5h to drive 470 km from Sudbury to Brantford.For part of the trip, he drove at 100 km\h. For the rest of the trip, he drove at 90 km\h. How far did he drive at each speed?
:
First, find out how long he drove at each speed.
Let = time at 100 km/hr
total time was given as 5 hrs therefore:
(5-t) = time at 90 km/hr
:
Write a distance equation: Dist = speed * time
;
dist at 100 km/hr + dist at 90 km/hr = 470 km
100t + 90(5-t) = 470
:
100t + 450 - 90t = 470
:
100t - 90t = 470 - 450
:
10t = 20
t =
t = 2 hrs at 100 km/hr
therefore
2 * 100 = 200 km at 100 km/hr
:
I'll let you find the dist at 90 km/hr