Corresponding sides are a pair of matching sides in two different shapes (size does not matter). In the field of geometry, the concept of corresponding sides plays an important role to prove various triangular theorems.
The Boeing B-17 Flying Fortress is a four-engine heavy bomber aircraft developed in the 1930s for the United States Army Air Corps (USAAC).
The Boeing B-17 Flying Fortress and the Consolidated B-24 were the United States' two standard heavy bombers until the arrival of the Boeing B-29 Superfortress in 1944. The B-17 served in almost every theater of World War II, but it used mostly by the US Eighth Air Force, based in the UK, to bombard German targets.