Simultaneous equations like 𝒚 = 2𝒙 - 1 and 𝒚 = 𝒙 + 1 can be represented graphically. To solve the equations graphically, the two lines 𝒚 = 𝒙 + 1 and 𝒚 = 2𝒙 - 1 are drawn on the same diagram.

Be careful to note what a GCSE question is asking. If it states ‘solve algebraically’ then you must do so. To find solutions from graphs, look for the point where the two graphs cross one another.

Simultaneous linear equations are used to model situations where two relationships must be satisfied at the same time. These problems often involve two interdependent variables, such as comparing ...