Make the formulas memorable with a simple-to-create foldable that students can look back to in their notes. My grade 10 academic math class (MPM2D) found these very handy during the analytic geometry unit.
While the formulas for a line segment's slope, length, and midpoint should definitely be discovered/motivated by discussing rise and run, applying the Pythagorean Theorem etc., students still have some trouble keeping straight when to add and when to subtract coordinates.
Your academics will enjoy doing a bit of cut and pasting like in elementary days of old!
-> template you can print for students to cut out, fold, cut, and label
-> answer / example.
You could use this simple foldable template for many topics. It's nothing fancy, but I thought I'd share to save you the time creating it.