1 lgi thxu so much guys

(a + x)² = a² + 8a + 16
a² + x² + 2ax = a² + 8a + 16
x² + ax = 4a + 16
x² + x = 4 + 16
x² + x = 20
x = 4

Jawaban : C

Maaf kalau salah
Jadikan terbaik ya, makasih

(a + x)² = a² + 8a + 16
(a + x)² = (a + 4)(a + 4)
(a + x)² = (a + 4)²

x = 4 (C)