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.

Given any cubic or quartic equation with real coefficients, it can be transformed by a change of variable into a standard form, and thus solved by means of a double-sided scale (Fig. 1) in the case of ...

SOME years ago you published some interesting communications in regard to the graphical solution of cubic and quartic equations (vol. lxi. p. 55, vol. lxiii. pp. 515 and 609, vol. lxiv. p. 5). The ...