Right-angled triangle measure of whose sides are integers
Source: IMO Longlist 1989, Problem 24
September 18, 2008
geometryquadraticsnumber theory unsolvednumber theory
Problem Statement
Let be positive integers such that ab \equal{} cd and a\plus{}b \equal{} c \minus{} d. Prove that there exists a right-angled triangle the measure of whose sides (in some unit) are integers and whose area measure is square units.