91² = (90 + 1)² = 90² + 2 * 90 * 1 + 1² = 8100 + 180 + 1 = 8281
69² = (70 - 1)² = 70² - 2 * 70 * 1 + 1² = 4900 - 140 + 1 = 4761
102² = (100 + 2)² = 100² + 2 * 100 * 2 + 2² = 10000 + 400 + 4 = 10404
48² = (50 - 2)² = 50² - 2 * 50 * 2 + 2² = 2500 - 200 + 4 = 2304
89² = (90 - 1)² = 90² - 2 * 90 * 1 + 1² = 8100 - 180 + 1 = 7921
35² = (30 + 5)² = 30² + 2 * 30 * 5 + 5² = 900 + 300 + 25 = 1225
65² = (60 + 5)² = 60² + 2 * 60 * 5 + 5² = 3600 + 600 + 25 = 4225
125² = (100 + 25)² = 100² + 2 * 100 * 25 + 25² = 10000 + 5000 + 625 = 15625
91² = (90 + 1)² = 90² + 2 * 90 * 1 + 1² = 8100 + 180 + 1 = 8281
69² = (70 - 1)² = 70² - 2 * 70 * 1 + 1² = 4900 - 140 + 1 = 4761
102² = (100 + 2)² = 100² + 2 * 100 * 2 + 2² = 10000 + 400 + 4 = 10404
48² = (50 - 2)² = 50² - 2 * 50 * 2 + 2² = 2500 - 200 + 4 = 2304
89² = (90 - 1)² = 90² - 2 * 90 * 1 + 1² = 8100 - 180 + 1 = 7921
35² = (30 + 5)² = 30² + 2 * 30 * 5 + 5² = 900 + 300 + 25 = 1225
65² = (60 + 5)² = 60² + 2 * 60 * 5 + 5² = 3600 + 600 + 25 = 4225
125² = (100 + 25)² = 100² + 2 * 100 * 25 + 25² = 10000 + 5000 + 625 = 15625