Preparing Proofs in Coordinate Geometry
In the seventeenth century, the French mathematician Rene Descartes applied algebraic principles to geometric situations. This blending of algebra and geometry is referred to as analytic geometry. Because this process often involves placing geometric figures in a coordinate plane, it is also more commonly known as coordinate geometry.
Coordinate geometry proofs employ the use of formulas such as the Distance Formula, the Slope Formula and/or the Midpoint Formula as well as postulates, theorems and definitions.
When developing a coordinate geometry proof:
- draw and label the graph
- state the formulas you will be using
- show ALL work (if you are using your graphing calculator, be sure to show your screen displays as
- part of your work.)
- have a concluding sentence stating what you have proven and why it is true.
Example 1:
Example 2:
