Chapter 4

USE ANOTHER BROWSER TO SEE ALL OF MY VIDEOS.

See videos in order, or for particular sections in the textbook. The labeling of each video (4V1, 4V2, etc.) is for students in my class. Students need to copy the contents of each video for their Video Notebook if it has a label.  If there is not label, then it's optional for you view it. You do not include notes for that video in the VN.  Label top of each page with the Video Label given for each video.

4.1

Overview of Systems of Equations parts 1 & 2 -The Overview shows all three methods of solving this system, derived from a word problem: y = 2x and x + y = 9 

4V1: Overview Part 1 

http://www.youtube.com/watch?v=pq1kF_DgHmQ 

4V2: Overview Part 2 

http://www.youtube.com/watch?v=4IrJRwfKMUg 

4V3: Solving Systems of Equations by Graphing Part 1

Solve this system by graphing: y = —3x and 2x — y = —6  

http://www.youtube.com/watch?v=FtUl8ECisoE 

4V4: Solving Systems of Equations by Graphing Part 2 

http://www.youtube.com/watch?v=dqzg4G3lnjU 

4.2

4V5: Solve System by Substitution - part 1 

This is part 1 of how to solve a system of equations using the substitution method. 

The first system solved is 2x - y = -5 and y = x + 4. 

The second system solved is 3x + y = -14 and 4x + 3y = -22. 

http://www.youtube.com/watch?v=ZqEDFqX4OwE 

4V6: Solve System by substitution - part 2 

This is part 2 of how to solve a system of equations using the substitution method. It covers special cases--a dependent system when the 2 equations are the same, and therefore the solution is infinitely many ordered pairs. The other is an inconsistent system, so there is no solution. 

http://www.youtube.com/watch?v=1hsE9KYKA5g 

4.3

4V7: Solving Systems of Equations using the Addition Method Part 1 

http://www.youtube.com/watch?v=HJbYUGWJvDc 

4V8: Solving Systems of Equations using the Addition Method Part 2 

http://www.youtube.com/watch?v=DfzFn_Etg9Q 

4.4 

Basic Word Problems using 2 variables

4V9: Part 1: http://www.youtube.com/watch?v=4mx0IKfepJg

OPTIONAL: If you want to see more examples, watch Part 2: http://www.youtube.com/watch?v=fld8pMLht9g

These two videos focus on how to define two variables, set up two equations, and check the solutions.  Problems are presented, but using the methods of graphing, substitution, and addition to solve the problems are NOT shown.

4V10: Part 1: http://www.youtube.com/watch?v=IDmyacLkWA8

OPTIONAL: If you want to see more examples, watch Part 2: http://www.youtube.com/watch?v=_A_niyNpCRk

Rate of Wind or Current Problems

4V11: Rate of Wind Problem #1

http://www.youtube.com/watch?v=cf0oUu04sCM

OPTIONAL: If you want to see another example, watch Rate of Wind Problem #2: A plane flying against the wind flew 270 miles in 3 hours.  Flying with the wind, the plane traveled 260 miles in 2 hours.  Find the rate of the plane in calm air and the rate of the plane.  

http://www.youtube.com/watch?v=P1aghAIDjGc

4V12: Rate of Current Problem #2

http://www.youtube.com/watch?v=cy3qjHiNOfs

OPTIONAL: If you want to see another example, watch: Rate of Current Problem #3 

http://www.youtube.com/watch?v=03F0mhQruso

Value Mixture Problems

4V13: Value Mixture #1: This video shows how to solve the following mixture problem using algebra by writing a system of equations with 2 variables. Problem: Mia wants to make a punch by mixing some apple juice costing $2.25 per quart with cranberry juice costing $3.25 per quart. How many quarts of each should she use if she wants to make 100 quarts costing $2.50 per quart?

http://www.youtube.com/watch?v=zTu3VO0Erx0

Other Problems