Peresamaan garis singgung lingkaran x2 + y2 – 4x – 6y -27 = 0 di titik (8,5) adalah . . . .

x²+y²-4x-6y-27=0
A = -4
B = -6
C = -27

titik(8,5)
x1 = 8
y1 = 5

XX1 + YY1 + (A/2)(x+x1) + (B/2)(y+y1) + C = 0
8x + 5y + -2(x+8) + (-3)(y+5) + (-27) = 0
8x + 5y -2x -16 -3y -15 -27 = 0
6x + 2y-58 = 0