
To find: value of n
We know,



So, according to question:






⇒ (n + 5) (n + 4) = 22 (n – 1)
⇒ n2 + 4n + 5n + 20 = 22n – 22
⇒ n2 + 9n + 20 - 22n + 22 = 0
⇒ n2 – 13n + 42 = 0
⇒ n2 – 6n – 7n + 42 = 0
⇒ n(n – 6) – 7(n – 6) = 0
⇒ (n – 7) (n – 6) = 0
⇒ n = 7 or 6
∴ The value of n can either be 6 or 7