5x2 – 22x – 15 = 0

(xi) 5x² – 22x – 15 = 0

Sol. 5x² – 22x – 15 = 0

∴  5x² – 25x + 3x – 15 = 0

∴  5x(x – 5) + 3(x – 5) = 0

∴  (x – 5) (5x + 3) = 0

∴  x – 5 = 0 or 5x + 3 = 0

∴  x = 5 or 5x = –3

∴  x = 5 or x = ^–3/₅