0580
Forming and Solving Equations
Algebra and Sequences
Finishing the question
- The value of the letter is rarely the answer on its own: the question asked about the situation
- Convert back to what was asked, with units and the quantity named
- Where the question asks for a different quantity from the one you called x, substitute to find it
- Reject any solution the context forbids, such as a negative length or a fractional number of people