Key learning points

1. It is possible to find a solution that satisfies a problem with two unknowns by trial and error.
2. It is possible to use the difference between the two scenarios to create a third valid scenario.
3. Once you know one of the unknowns, you can substitute to find the other.

Keywords

• Simultaneous equations - Equations which represent different relationships between the same variables are called simultaneous equations.

• Elimination - Elimination is a technique to help solve equations simultaneously and is where one of the variables in a problem is removed.

Common misconception