HKDSE-MATH - 2020 - Paper 1 -

Ans: (a) $(x-10)^2 + (y + 15)^2 = 625$ (b) (i) $\Gamma$ is para

Ans: C
I is true. Rewrite the equation of $C_1$, then the equa

Ans: D
$\left\{\begin{array}{ll}
x^2 + y^2 -6x + cy -7 =0 �

Ans: (a) $10$ (b) Yes (c) $120$

1. Centre of $G$

   $\begin{array}

Ans: C

Let $C$ be the centre of the circle. Then the coordinat

Ans: A

$\left\{ \begin{array}{l}
x^2 +y^2 -4x -22y +75 = 0 &#

Ans: (a) $20$ (b) (i) $GH$ is perpendicular to $GP$. (ii) $22

Ans: (a) $4x+3y-668=0$ (b) $(110,76)$ (c) $(x-128)^2+(y-

Ans: C

Let $x^2+y^2+Dx+Ey+F=0$ be the equation of $C$. Sinc

Ans: (a) $\Gamma$ is the perpendicular bisector of $AB$. (b

Ans: C

I is not true. Note that the coordinates of $G_1$ and $G

Ans: A

Note that $(1,0)$ lies on $hx+ky=6$, we have

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