Question

Resolva as equações:
(3n- 15)!= 720

Answer 1

$6! = 6.5.4.3.2.1 = 720$

$(3n - 15)! = 720 \\ (3n- 15) \cancel! = 6 \cancel! \ \\ 3n - 15 =6 \\ 3n = 15 + 6 \\ 3n = 21 \\ n = \frac{21}{3} \\ \boxed{n = 7}$