Need help preparing for Euclid contest

AFG34

I'm writing the Euclid contest this April so i went to their website and downloaded the 2007 version. I don't know how to solve problems similar to questions 7. b), 8. b), and 10. I have never been taught how to do these problem so I'm asking you guys if you know a link to some website where i can learn to solve these types of questions.

awvvu

What's wrong with reading the solutions they have? They're all geometry problems and just require experience with working out problems like that.

Werg22

You will need to know the basic circle theorems and exercise plenty. I recommend you buy the three volumes of 'Problems, Problems, Problems' and practice (conveniently, the problems are listed from easiest to hardest).

You should also write past contests, all while timing yourself.

A good strategy to adopt while writing the contest is to allocate time to improving and clarifying your answers rather than to trying to solve a problem for which you see no immediate clue to its solution. Seven well-written solutions are better than ten poorly-written ones, albeit correct.

Good luck.

mathwonk

you need to know about ratios of sides of similar triangles, and the fact that a triangle with two sides tangent to a circle is isosceles, i.e. that both tangent lines to a circle from a point outside the circle have the same length.