Find the equation of the chord of contact from (1,2)(1, 2)(1,2) to x2+y2=5x^2 + y^2 = 5x2+y2=5.
x+2y=5x + 2y = 5x+2y=5
x+y=5x + y = 5x+y=5
2x+y=52x + y = 52x+y=5
x+2y=1x + 2y = 1x+2y=1