Two tangent circles, a chord towards the tangency point and a tangent. What’s the proportion a : b in terms of radii R and r?

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## Solution

The proportion a : b is √(R/(R+r)).

## Poem

The steam locomotive

A jewel of the railway birth

Rack and pinion locomotive

Pulled so many wagons

And made us people happy

Powerfull machine

Very popular at altitude

They accompanied our travels

Our dreams of escape

Our love stories and our tears

The steam loco so friendly

## One reply on “The steam locomotive”

My Solution to The steam locomotive, with STEWART Theorem.