MathematicsClass 7Simple Equations
Transposition Method
Simplifying equation solving by moving terms from one side to the other with inverted signs.
Class 7 · MathematicsCBSE & ICSE
Definition
The transposition method is a shortcut for solving equations where a term is moved from one side of the equation to the other. When a term is transposed, its mathematical sign changes to its opposite (positive becomes negative, multiplication becomes division, and vice versa). This simplifies the process of isolating the variable.
Worked examples
1
In solving x + 5 = 12, transpose +5 to the RHS to get x = 12 - 5, which simplifies to x = 7.
2
In solving 2x - 3 = 7, transpose -3 to get 2x = 7 + 3, so 2x = 10, then transpose 2 to get x = 10/2 = 5.
3
In solving 5y = 35, transpose multiplication by 5 to division to get y = 35/5, which gives y = 7.
Common mistakes
- • Forgetting to change the sign of a term when moving it across the equals sign.
- • Transposing only a part of a term or confusing the rules for addition/subtraction with multiplication/division.