This jingle has helped generations of algebra students recall the quadratic formula that solves every equation of the form $latex ax^2+bx+c=0$. The formula is as ...

Three lines of symmetry on an equilateral triangle. Right-angled triangles follow the same rules as other triangles. It's not the right angle that matters but whether the triangle is scalene or ...

There's a part of the brain that enables us to perceive magnitude -- we can compare loudness when hearing different tones or compare the number of dots in a group at a glance. Neuroscientists have ...

We are fond of saying things are symmetric, but what does that really mean? Intuitively we have a sense of symmetry as a kind of mirroring. Suppose we draw a vertical line through the middle of a ...