Let A(1,0), B(2,-1) and C(73,43) be three points. If the equation of the bisector of the angle ABC is αx+βy=5, then the value of α2+β2 is [2026]
(1)
BDDC=ABAC=2×352=35
D=(128,48)=(32,12)
Slope of AD=-3/21/2=-3
3x+y=5
α=3, β=1; α2+β2=10