Ok welcome to the lesson on direct and inverse variation.  This topic will use your knowledge of proportions so go back and review proportions if you don’t really understand them.  Variation is how “variables” relate to one another and how we express this in math by a proportion.  Direct and inverse variation problems are also very common in science (as formulas) so you want to really pay attention to the lesson.

Things to focus on this lesson:

• the direct variation formula
• the inverse variation formula
• how to solve variation problems by using given information and the direct/inverse variation formula

#### Direct and Inverse Variation

how are you getting ready for the future? do you have a plan for all the areas of your life?

 Nice work! you finished lesson 3 here are some things you should be able to do:* explain the concept of variation* solve proportions by using the cross-product* solve direct and inverse variation problemsNow that you understand variation the last lesson will be about simplifying rational expressions- this lesson is a little difficult for most students so be prepared to work a bit harder Lesson 4:  Simplifying Rational Expressions 