S2 · Algebra · ALG.SYSTEM.2X2
Solve 2×2 linear systems
Solve linear systems
Intuition
Understand first, compress later.
Algebra describes structures generally: a symbol stands for a number, while the rules remain the same.
Switch representations
Linear functionf(x) = x
graph of fΔx (run)Δy (rise)y-intercept
Formal view
You can solve linear systems when you can recognise the underlying objects, select valid rules and check each step for equivalence or logical implication.
Why does it work?
This skill sits on a prerequisite network. If a step is unstable, repair the missing prerequisite instead of merely doing more items of the same type.