Algebra, Lesson 1
Equality Is a Relationship
Keep both sides equal while you uncover the value of x.
Predict first. Then move one value and watch every representation respond.
Where do you expect the two sides to match?
Choose a value of x.
Subtract the same amount from both expressions. Watch the matching value of x.
The comparison will appear after you commit to a prediction.
Check the matching idea
Answer all five questions. Explanations stay hidden until the whole set is complete.
Test the equation again
Move x until the two expressions reach the same value.
The left side is too small.
Check the solution idea
Choose one answer for every question, then reveal the complete reasoning.
What kind of equation is this?
Use the three standard algebra terms. Ask how many values make the equation true.
Try values of x and ask: some, every, or none?
Classify equations
Complete all five classifications before checking the standard terms.
The move that matters
Choose equality-preserving moves
Decide which transformations keep exactly the same solutions.
Next: test a picture.
Geometry turns dragging into a search for what must stay true.