Question 449750: One day, you are rollerblading on a trail while it is windy. You travel
along the trail, turn around and come back to your starting point. On your way out
on the trail, you are rollerblading against the wind. On your return trip, which is the
same distance, you are rollerblading with the wind. You can only travel 3 miles an
hour against the wind, which is blowing at a constant speed. You travel 8 miles an
hour with the wind. Use the models below to write and solve a system of equations
to find the average speed when there is no wind and the speed of the wind.
Against the wind: Your speed with no wind - Speed of wind = Your speed
With the wind: Your speed with no wind + Speed of wind = Your speed
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! On your way out on the trail, you are rollerblading against the wind.
On your return trip, which is the same distance, you are rollerblading with the wind.
You can only travel 3 miles an hour against the wind, which is blowing at a constant speed.
You travel 8 miles an hour with the wind.
:
Seems like they are making this more complicated than necessary
:
Let s = speed with no wind
Let w = speed of the wind
:
Write an equation with the wind and an equation against the wind
s + w = 8
s - w = 3
---------------add these two equation, eliminates w, find s
2s + 0 = 11
2s = 11
s = 
s = 5.5 mph when there is no wind
then
5.5 + w = 8
w = 8 - 5.5
w = 2.5 mph is the wind
therefore
5.5 + 2.5 = 8 mph with the wind
and
5.5 - 2.5 = 3 mph against
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