a) 37² + 37 * 13 = 37 * 37 + 37 * 13 = 37 * (37 + 13) = 37 * 50 = 1850
б) 25² - 25 * 15 = 25 * 25 - 25 * 15 = 25 * (25 - 15) = 25 * 10 = 250