103² = (100 + 3)² = 10000 + 600 + 9 = 10609
(63² - 729)/(83² - 79²) = (63² - 27²)/(83²- 79²) = (63 - 27)(63 + 27)/(83 - 79)(83 + 79) = 36*90/4*162 = 4*9*9*10/4*2*9*9 = 10/2 = 5
103² = (100 + 3)² = 10000 + 600 + 9 = 10609
(63² - 729)/(83² - 79²) = (63² - 27²)/(83²- 79²) = (63 - 27)(63 + 27)/(83 - 79)(83 + 79) = 36*90/4*162 = 4*9*9*10/4*2*9*9 = 10/2 = 5