Question

Gan bathin dong pake cara

Answer 1

25^(x - 1) + 4.5^x - 21 = 0
25^x . 25^-1 + 4.5^x - 21 = 0
misal:
5^x = a
a²/25 + 4a - 21 = 0
a² + 100a - 525 = 0
(a - 5)(a + 105) = 0
ambil a = 5 maka
5^x = 5
x = 1