Question

materi lingkaran kelas 11 ​

Answer 1

❐ Lingkaran Analitika

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x² + y² + Ax + By + c = 0

—

x = 0, y = 5

0² + 5² + 0(A) + 5B + c = 0

25 + 5B + c = 0

—

x = -1, y = 0

(-1)² + 0² - A + 0(B) + c = 0

1 - A + c = 0

A = 1 + c

—

x = 5, y = 0

5² + 0² + 5A + 0(b) + c = 0

25 + 5A + c = 0

25 + 5(1 + c) + c = 0

25 + 5 + 5c + c = 0

6c = -30

c = -5

—

A = 1 + c

A = 1 - 5

A = -4

—

25 + 5B + c = 0

25 + 5B - 5 = 0

5B = -20

B = -4

—

x² + y² + Ax + By + c = 0

x² + y² - 4x - 4y - 5 = 0

r² = (A/2)² + (B/2)² - c

r² = (-4/2)² + (-4/2)² - (-5)

r² = 4 + 4 + 5

r² = 13

r = √13 (C)