Tolong yang bisa sekalian sama jalannya cara dapetnya gimana

y = x² - 2x - 3

Refleksi thdp x = 4

x' = 2k - x
x = 2k - x'
x = 2(4) - x'
x = 8 - x'

Subtitusikan

y = (8 - x')² - 2(8 - x') - 3
y = (8 - x')² + (8 - x') - 3(8 - x') - 3
y = (8 - x)² + (8 - x) - 3(8 - x) - 3
y = (8 - x)(8 - x + 1) - 3(8 - x + 1)
y = (8 - x - 3)(8 - x + 1)
y = (5 - x)(9 - x)
y = x² - 14x + 45
⬇
y = x² - (9 + a) + 9a

9a = 45
9 + a = 14

Didapat a = 5