Skill: one-two-step-equations
Lab: Balance-Scale Solver
Solve equations on a balance scale: apply any operation to both sides and watch the scale stay level until x stands alone.
Balance the equation: 2x + 3 = 11
Moves: 0. Goal: get x alone.
2x + 3 = 11
Try it
Challenge: solve 2x + 3 = 11 in exactly 2 moves.
Press Reset, then choose the two inverse operations in reverse order.
Not solved yet.
What to notice: the scale never tips — both pans always match, because every move hits both sides. Solving is just choosing moves that peel the equation down to x.
Strategy
Undo +/− before ×/÷ (reverse PEMDAS). Each move replaces the equation with a simpler equivalent one. When a pan holds only x, you are done — then verify by substitution.