For tips on how to do this, look at Factorising quadratics and Factorisation of further quadratics in this guide. For (\({x}\) + 2)(\({x}\) + 7) to equal 0 either the first or second bracket must be ...

Scientific American is part of Springer Nature, which owns or has commercial relations with thousands of scientific publications (many of them can be found at www ...

Plotting a graph takes time. Often mathematicians just want to know the key features. These are: shape, location and some key points (such as where the graph crosses the axes or turning points).

Everyone learns (and some readers maybe still remember) the quadratic formula. It’s a pillar of algebra and allows you to solve equations like Ax 2 +Bx+C=0. But just because you’ve used it doesn’t ...