
Expression trees: the structure of terms
An expression drawn as a tree: whatever hangs lowest is calculated first. The order of operations stops being a rule and becomes visible.
MathematicsGrade 5–10
Make the structure of terms visible, interpret algebraic manipulation geometrically and solve equations algebraically and graphically.

An expression drawn as a tree: whatever hangs lowest is calculated first. The order of operations stops being a rule and becomes visible.

The three binomial formulas as areas: a square splits into smaller squares and rectangles.

Solve linear equations on a balance: whatever you do to both sides keeps the scale balanced.

Two equations are two lines. Their point of intersection is the solution, which you can read off and check.

Draw both sides of an equation as graphs. The solutions are where the graphs cross.