Solve : 5m² - 22m-15 = 0
5m² - 22m - 15 = 0
∴ 5m² - 25m + 3m - 15 = 0
∴ 5m (m - 5) + 3(m - 5) =0
∴ (m - 5) (5m + 3) = 0
∴ m - 5 = 0 or 5m + 3 = 0
∴ m = 5 or m = −3 / 5
