Solving linear equations on the balance
An equation is a balance. Try values, then solve equations with x on one or both sides, fractions and brackets by doing the same to both pans, and change the subject of a formula.
- UK: Year 8
- France: grade 7
- Germany: grade 6
- Iran: grade 7
- Afghanistan: grade 8
- Syria: grade 6
- Palestine: grade 7
- Ukraine: grade 6
- Russia: grade 6
Guide
This studio follows KS3 algebra: solving linear equations in one variable, including all forms that need rearrangement, and changing the subject of a formula.
An equation such as 3x + 2 = 14 is like a balance: the two sides weigh the same. x is the unknown; the solution is the number that makes both sides equal.
The tiles: a green strip is x, a yellow square is 1, and a red tile is negative. A white and a red tile of the same shape cancel each other (a zero pair).
The golden rule: whatever you do to one pan, do to the other. A move on one pan only tips the scale.
Choose a move below the scale (add or take away a tile, × or ÷ by a number), then tap a pan, or Both pans. Each level equation is written above the scale, one step under another.