Implications for Instruction
Audience and Prerequisite: The audience
should be high school students in an Algebra II course. They should have prior
knowledge of solving linear equations on a graphing calculator, solving linear
equations by hand, solving inequalities by hand, and solving absolute value
equations.
Each of these activities are designed to teach students about
how to solve inequalities using a graphing calculator. Activity 1 is a great
way to transition from learning how to solve linear equations to solving inequalities.
The activity should allow students to see that similar methods are used to solve
inequalities. Students should learn how to manipulate variables and become familiar
with the properties of inequality symbols.
Activity 1: Solving Inequalities, has real world applications. An example of
a real world problem would be:
Chase has a maximum of $10.50 to spend at the candy store. She buys some Twix and Snickers for a total of $1.55. She then strolls through the store and sees a sign that says she can buy cotton candy for $1.35 per pound. How many pounds of cotton candy can Chase? (Round to the nearest tenth.)
Activity 2 can be taught after students learn how to solve inequalities and
how to solve absolute value equations. This is best considered an extension
activity after practice solving algebraically absolute value inequalities. This
activity will help to build on already established knowledge. It will allow
students to see how mathematics is connected.
The TI-83 graphing calculator is used in both activities. It
is important for students to be able to manipulate the use of a graphing calculator.
In today’s society, students are expected to learn as much technology
as they can. We are getting students prepared for careers and jobs that have
not been created yet. The graphing calculator allows for students to see how
mathematics and technology are related. Students should feel more comfortable
with the graphing calculator after these activities. The graphing calculator
is used simply as an extension to the knowledge that they should have learned
from solving the equations by hand. This will not be used for the students to
allow the calculator to do the work for them but to simply to enhance their
understanding of inequalities.