Algebra 2
Section 3.6: Problem Solving: Using Systems
Example: If 8 pens and 7 pencils cost $3.37 while
5 pens and 11 pencils cost $3.10, how much does
each pen and each pencil cost?
1) Define the variable(s)
2) Write an equation (in this case...a system of equations)
3) Solve the system
4) Write a sentence
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Algebra 2
Section 3.6: Problem Solving: Using Systems
Look in your book at the bottom of Page 131:
Air Speed: The speed of an aircraft in still air
(no wind acting upon it)
Wind Speed: The speed of the wind
Tail Wind: a wind blowing in the same
direction as the path of the aircraft
...you would be traveling faster (in relation to the ground)
Ground Speed = Air Speed + Wind Speed
Head Wind: a wind blowing in the opposite
direction as the path of the aircraft
...you would be traveling slower (in relation to the ground)
Ground Speed = Air Speed - Wind Speed
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Algebra 2
Section 3.6: Problem Solving: Using Systems
Example: With a tail wind, a helicopter traveled
300 miles in 1 hour 40 minutes. The return trip
against the same wind took 20 minutes longer.
Find the wind speed and also the air speed of the
helicopter. (Remember: Distance = Rate • Time )
1) Define the variable(s)
2) Write an equation (in this case...a system of equations)
3) Solve the system
4) Write a sentence
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Algebra 2
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