make right triangles
find the length of the diagonal on the ground then find the length of the diagonal from corner to corner (see diagram
actually, I found a neat thing
see diagram
remember the pythagorean theorem
so, if the legs of a right triangle=a and b and the hyptonuse is c then
a²+b²=c²
alright, so we look at the diagram now
a²+b²=k²
and
c²+k²=d²
but, k²=a²+b²
so
a²+b²+c²=d²
a=15
b=20
c=60
15²+20²+60²=d²
225+400+3600=d²
4225=d²
65=d
the longest stick is 65cm assuming it has no width
