ABCDEF is a regular hexagon Where, AB=a BC = b CD = ?
∵ ABCDEF is regular hexagon, then AB = ED, BC = FE and CD = AF Now, we know that AD=2BC=2b and in ΔABC AC = AB + BC [Using triangle law] = a + b Now, In ΔACD AC + CD = AD ⇒ a + b + CD = 2b ⇒ CD = 2b - a - b ⇒ CD = b - a