geometry
posted by c .
A rectangle is 80 cm long and 20 cm wide. Find, to the nearest degree, the acute angle formed at the intersection of the diagonals.

take one of the rightangled triangles, call the base angle Ø
tanØ = 20/80 = 1/4
Ø = appr. 14.04°
can you take it from there?
I see pairs of isosceles triangles !