How did Apollo 13 return back to earth?

Apollo 13 returned to Earth after a critical failure in its service module, which caused an oxygen tank to explode. The crew used the lunar module, Aquarius, as a "lifeboat" for life support and navigation as they executed a slingshot maneuver around the Moon to gain the necessary speed and trajectory to return home. The mission control team devised a series of maneuvers and calculations to ensure the spacecraft could re-enter Earth's atmosphere safely. Ultimately, the crew successfully splashed down in the Pacific Ocean on April 17, 1970.