Centre of circle is O≡(1,−2) Radius of circle is r=√12+4+11=4 OD‌=√r2−AD2 ‌=√16−3=√13 OD=√13= Length of perpendicular from (1,−2) upon 2x+3y+k=0 ‌√13=‌
|2−6+k|
√13
‌|k−4|=13 ‌k−4=±13 ‌k=17‌ and ‌−9 ∴ Sum of values of k=17−9=8
