Graphing proportional relationships

The  exercise appears under the 8th Grade Math Mission. This exercise emphasizes that proportional relationships grow through the origin and are linear.

Types of Problems
There are three types of problems in this exercise:


 * 1) Graph and give the descriptions: This problem gives the student a proportional relationship and asks them to graph it and select appropriate summaries from a multiple select list.Gpr1.png
 * 2) Graph and find the equation: This problem gives the student a proportional relationship and asks them to graph it and find the equation of the relationship.thumb|Graph and find the equation
 * 3) Graph and find the slope: This problem gives the student a proportional relationship and asks them to graph it and find the unit change which is effectively the slope.thumb|Graph and find the slope

Strategies
Necessary skills include an ability to graph lines. Knowing the concepts of direct variation should provide an advantage on this exercise.
 * 1) Direct variation is modeled by y=kx.
 * 2) The graph of direct variation is always linear and always goes through the origin.

Real-life applications

 * 1) Direct variation (along with it's counterpart inverse variation) are at the core of many physics applications.