1) The circle passing through (1,-2) and touching the axis of x at (3,0) also passes through the point A) (-5,2) B) (2,-5) C) (5,-2) D) (-2,5) Answer: Option CExplanation: Let the equation of circle be (x−3)2+(y−0)2+λy=0 As it passes through (1,-2) ∴ (1−3)2+(−2)2+λ(−2)=0 ⇒ 4+4−2λ=0⇒λ=4 ∴ (x−3)2+y2+4y=0 By hit and trial method, we see that point(5,-2) satisfies equation of circle.