Diketahui lingkaran L = x2 + y2 + 4x – y = 36, tentukan:

Persamaan Lingkaran

Transformasi Geometri

x² + y² + 4x – y – 36 = 0

Jari-jari = r² = (-1/2 A)² + (-1/2 B)² – C

P = (-1/2 A, -1/2 B)

P = (-1/2 .4, -1/2 (-1))

Pusat = (-2, 1/2)

r² = (-1/2 .4)² + (-1/2 . (-1))² – (-36)

r² = 4 + 1/4 + 36

r² = 161/4

Luas lingkaran = πr² = 22/7 × 161/4 = 253/2 sL

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P(-2,1/2)

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

y' = 5y = 5. 1/2 = 5/2

Persamaan lingkrn hsl trasformasi

P(-4,5/2) dan r² = 161/4

(x – (-4))² + (y – 5/2)² = 161/4

x² + 8x + 16 + y² – 5y + 25/4 – 161/4 = 0

x² + y² + 8x – 5y – 18 = 0 ✔