Post 7: Solving One Step Equations

When they enter the next room, they realize they are standing on a literal balance scale with an x-weight on one side. One of the kids adds a 3-weight to only one pan — a miscalculated equation — which makes gravity violently tilt, tossing Sage briefly into the air. The nearby kids scatter for cover at the tremor, clearly used to ducking for exactly this reason. Mirroring the same weight onto both pans settles it level, and one of the kids, watching from behind a rock, visibly relaxes when the room stops shaking. The equation has to stay balanced at all times, or the ground turns against all of them, not just her. The tremor also sends the shadowy figure ducking behind a stretch of rubble at the edge of the room.

This experience reminds the group that when trying to solve a one-step equation, you have to keep the equation in balance at every step. Since the main goal is to isolate the variable to one side of the equation, the way to keep both sides in balance is by using inverse operations.

Addition and subtraction are inverse (or opposite) operations.

Multiplication and division are inverse (or opposite) operations.

Great job! The group can now move forward.

Click here for the next post

Catch your algebra mistakes before they cost you

The scratchpad in this guide runs on moment.of.math — a free Chrome extension that checks your algebra line by line, on any problem. It can generate new variations problems, so you can get as much practice as you need. On many homework sites, it automatically detects the math on the page, so you don't have to copy anything over. Try it on tonight's homework.

Add to Chrome