Systems of linear equations word problems

The  exercise appears under the 8th Grade Math Mission. This exercise uses systems of equations to solve word problems.

Types of Problems
There is one type of problem in this exercise:


 * 1) Solve the word problem using a system: This problem provides a word problem in which there are two unknown quantities. The student is expected to create and use a system of equations to solve the problem.Soewp1.png

Strategies
Translating math into English and knowledge of the various ways to solve a system of equations (substitution, elimination and graphing) can help to ensure success on this exercise.
 * 1) The majority of the equations are set up so that substitution is the smoothest way to approach the problem.
 * 2) Research indicates answers will be positive integers in almost all cases, so "plugging in numbers" can be an efficient way to work the problem in some isolated cases.

Real-life applications

 * 1) These problems are word problems so the express possible real-life situations in which to use these techniques.
 * 2) In business, Cost, Revenue and Profit equations can be linear and finding equilibrium is essentially solving a word problem with systems of equations.