Question 19
The 36 points form a unit square grid. Polygon ABCDE has straight sides as shown. Its perimeter is $x+y\sqrt5+z\sqrt{13}$ units. Find $x+y+z$, with $x,y,z$ the nonnegative integer coefficients in this form. Use the two right triangles as aids. Source note: the triangle with legs 2 and 3 is incorrectly labelled $\sqrt5$ in the original; its hypotenuse is $\sqrt{13}$.
