Two circles and three coloured isosceles triangles. Prove that the circles are concentric.

Scroll down for a solution to this problem.

## Solution

The center of the large circle is the intersection of the perpendicular bisectors of the three triangles, and the center of the small circle is the intersection of the bisectors. Since they are isosceles, they are the same point.

This solution was provided by Ignacio Larrosa Cañestro.

## Poem

The gremlin

Evil little creature

Little elf with supernatural powers

He does not like the light neither the water

Neither the sun

Or food after midnight

The mogwai turned gremlin

By the magic

Of metamorphosis

Imaginary creature

He is a part of the mystery

In the horror movie