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Secondary 4 Additional Mathematics Preliminary Examination Paper 5

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Secondary 4 Additional Mathematics From Real Exams Generated by Qwen3.6 Plus Updated 2026-06-03

Questions

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TuitionGoWhere Practice Paper - Additional Mathematics Secondary 4

TuitionGoWhere Exam Practice (AI)
PRELIMINARY EXAMINATION 2024
Version 5 of 5

Subject: Additional Mathematics (4049)
Level: Secondary 4
Paper: 1
Duration: 1 hour 30 minutes
Total Marks: 80

Name: __________________________
Class: __________________________
Date: __________________________


INSTRUCTIONS TO CANDIDATES

  • Write your name, class, and date in the spaces provided.
  • Answer all questions.
  • Write your answers in the spaces provided in the question paper.
  • Give non-exact numerical answers correct to 3 significant figures, or 1 decimal place in the case of angles in degrees, unless a different level of accuracy is specified in the question.
  • The use of an approved scientific calculator is expected, where appropriate.
  • If the degree of accuracy is not specified in the question, and if the answer is not exact, give the answer to 3 significant figures.
  • Solutions by accurate drawing will not be accepted.

Section A [40 Marks]

Answer all questions in this section.

1. The line L1L_1 has equation y=2x+5y = 2x + 5. The line L2L_2 is perpendicular to L1L_1 and passes through the point A(4,1)A(4, -1). Find the coordinates of the point of intersection of L1L_1 and L2L_2.

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2. The curve CC has equation y=x26x+10y = x^2 - 6x + 10. (a) Express x26x+10x^2 - 6x + 10 in the form (xa)2+b(x - a)^2 + b.
[1]

(b) Hence, state the coordinates of the minimum point of the curve CC.
[2]

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3. A circle has centre C(3,2)C(3, -2) and radius 5 units. (a) Write down the equation of the circle in the form (xa)2+(yb)2=r2(x - a)^2 + (y - b)^2 = r^2.
[1]

(b) Show that the circle intersects the y-axis at two distinct points and find the coordinates of these points.
[3]

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4. The points A(2,3)A(-2, 3) and B(4,7)B(4, 7) are endpoints of a diameter of a circle. Find the equation of the circle in the form x2+y2+2gx+2fy+c=0x^2 + y^2 + 2gx + 2fy + c = 0.

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5. The line y=mx+3y = mx + 3 is a tangent to the curve y=x24x+7y = x^2 - 4x + 7. Find the possible values of mm.

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6. Find the coordinates of the stationary points on the curve y=x312x+5y = x^3 - 12x + 5 and determine the nature of each stationary point.

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7. The diagram shows a triangle ABCABC with vertices A(1,2)A(1, 2), B(5,6)B(5, 6), and C(7,0)C(7, 0). (Note: Diagram not to scale. Solutions by accurate drawing will not be accepted.)

Find the equation of the perpendicular bisector of the side ABAB.

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8. The curve y=4xy = \frac{4}{x} and the line y=x+3y = x + 3 intersect at points PP and QQ. Find the coordinates of PP and QQ.

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9. A circle passes through the origin O(0,0)O(0,0) and the points A(6,0)A(6,0) and B(0,8)B(0,8). Find the coordinates of the centre of this circle.

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10. The line LL has equation 3x4y+12=03x - 4y + 12 = 0. (a) Find the gradient of LL.
[1]

(b) Find the distance from the origin to the line LL.
[2]

<br> <br> <br> <br> <br> <br>

Section B [40 Marks]

Answer all questions in this section.

11. The curve C1C_1 has equation y=x2+2x3y = x^2 + 2x - 3. (a) Find the coordinates of the points where C1C_1 crosses the x-axis.
[2]

(b) Find the coordinates of the vertex of C1C_1.
[2]

(c) The curve C2C_2 is a translation of C1C_1 by the vector (04)\begin{pmatrix} 0 \\ 4 \end{pmatrix}. Write down the equation of C2C_2 and determine whether C2C_2 intersects the x-axis. Justify your answer.
[3]

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12. The points A(1,4)A(-1, 4), B(3,6)B(3, 6), and C(5,2)C(5, 2) are vertices of a triangle. (a) Show that triangle ABCABC is right-angled at BB.
[3]

(b) Find the area of triangle ABCABC.
[2]

(c) Find the equation of the circumcircle of triangle ABCABC.
[3]

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13. A circle CC has equation x2+y26x+8y11=0x^2 + y^2 - 6x + 8y - 11 = 0. (a) Find the coordinates of the centre and the length of the radius of CC.
[3]

(b) The line y=ky = k is a tangent to the circle CC. Find the possible values of kk.
[3]

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14. The curve y=x33x29x+10y = x^3 - 3x^2 - 9x + 10 has stationary points at AA and BB. (a) Find the x-coordinates of AA and BB.
[3]

(b) Determine the nature of the stationary point at AA where x>0x > 0.
[2]

(c) Find the equation of the tangent to the curve at the point where x=1x = 1.
[3]

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15. The line L1L_1 passes through the points P(2,5)P(2, 5) and Q(6,1)Q(6, 1). (a) Find the equation of L1L_1 in the form ax+by+c=0ax + by + c = 0.
[2]

(b) The line L2L_2 is parallel to L1L_1 and passes through the point R(0,3)R(0, -3). Find the equation of L2L_2.
[2]

(c) The line L3L_3 is perpendicular to L1L_1 and passes through the midpoint of PQPQ. Find the coordinates of the intersection of L2L_2 and L3L_3.
[4]

<br> <br> <br> <br> <br> <br> <br> <br> <br> <br> <br>

16. A circle C1C_1 has centre (2,3)(2, 3) and radius 4. A second circle C2C_2 has centre (8,3)(8, 3) and radius rr. (a) Given that the two circles touch externally, find the value of rr.
[2]

(b) Given instead that the two circles touch internally, find the possible values of rr.
[2]

(c) For the case where r=2r = 2 and the circles do not touch, find the range of distances between the centres for which the circles intersect at two distinct points.
[2]

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17. The curve y=2x28x+5y = 2x^2 - 8x + 5 is reflected in the y-axis to form curve CC'. (a) Find the equation of CC'.
[2]

(b) Find the coordinates of the minimum point of CC'.
[2]

(c) The line y=cy = c intersects CC' at two distinct points. Find the range of values for cc.
[2]

<br> <br> <br> <br> <br> <br> <br> <br>

18. The points A(1,1)A(1, 1), B(5,3)B(5, 3), and C(3,7)C(3, 7) form a triangle. (a) Find the gradient of ACAC.
[1]

(b) Find the equation of the altitude from BB to ACAC.
[3]

(c) Find the coordinates of the foot of the perpendicular from BB to ACAC.
[3]

<br> <br> <br> <br> <br> <br> <br> <br> <br> <br>

19. Consider the curve y=x2+kx+9y = x^2 + kx + 9. (a) Find the set of values of kk for which the curve lies entirely above the x-axis.
[3]

(b) Find the set of values of kk for which the line y=2xy = 2x intersects the curve at two distinct points.
[3]

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20. The diagram shows a rectangle OABCOABC where OO is the origin, AA lies on the x-axis, and CC lies on the y-axis. The point BB has coordinates (6,4)(6, 4). (Note: Diagram not to scale. Solutions by accurate drawing will not be accepted.)

(a) Find the equation of the diagonal OBOB.
[1]

(b) Find the equation of the diagonal ACAC.
[2]

(c) Find the coordinates of the intersection of the diagonals.
[1]

(d) A circle is drawn with OBOB as diameter. Find the equation of this circle.
[3]

<br> <br> <br> <br> <br> <br> <br> <br> <br> <br> <br>

END OF PAPER

Answers

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TuitionGoWhere Practice Paper - Additional Mathematics Secondary 4

Answer Key & Marking Scheme

Version 5 of 5

Section A

1. Gradient of L1L_1, m1=2m_1 = 2. Since L2L1L_2 \perp L_1, gradient of L2L_2, m2=12m_2 = -\frac{1}{2}. Equation of L2L_2: y(1)=12(x4)y+1=12x+2y=12x+1y - (-1) = -\frac{1}{2}(x - 4) \Rightarrow y + 1 = -\frac{1}{2}x + 2 \Rightarrow y = -\frac{1}{2}x + 1. Intersection: 2x+5=12x+12x + 5 = -\frac{1}{2}x + 1 2.5x=4x=1.62.5x = -4 \Rightarrow x = -1.6. y=2(1.6)+5=1.8y = 2(-1.6) + 5 = 1.8. Coordinates: (1.6,1.8)(-1.6, 1.8) or (85,95)(-\frac{8}{5}, \frac{9}{5}). [3 marks: 1 for grad L2, 1 for eq L2, 1 for coords]

2. (a) x26x+10=(x3)29+10=(x3)2+1x^2 - 6x + 10 = (x - 3)^2 - 9 + 10 = **(x - 3)^2 + 1**. [1 mark] (b) Minimum point at vertex. Coordinates: (3,1)(3, 1). [2 marks]

3. (a) Equation: (x3)2+(y+2)2=25(x - 3)^2 + (y + 2)^2 = 25. [1 mark] (b) At y-axis, x=0x = 0. (03)2+(y+2)2=25(0 - 3)^2 + (y + 2)^2 = 25 9+(y+2)2=259 + (y + 2)^2 = 25 (y+2)2=16(y + 2)^2 = 16 y+2=±4y + 2 = \pm 4 y=2y = 2 or y=6y = -6. Coordinates: (0,2)(0, 2) and (0,6)(0, -6). Since there are two distinct real solutions, it intersects at two points. [3 marks: 1 for sub x=0, 1 for solving, 1 for coords]

4. Midpoint (Centre) M=(2+42,3+72)=(1,5)M = (\frac{-2+4}{2}, \frac{3+7}{2}) = (1, 5). Radius squared r2=(41)2+(75)2=32+22=9+4=13r^2 = (4 - 1)^2 + (7 - 5)^2 = 3^2 + 2^2 = 9 + 4 = 13. Equation: (x1)2+(y5)2=13(x - 1)^2 + (y - 5)^2 = 13. x22x+1+y210y+25=13x^2 - 2x + 1 + y^2 - 10y + 25 = 13. x2+y22x10y+13=0x^2 + y^2 - 2x - 10y + 13 = 0. [4 marks: 1 for centre, 1 for r^2, 1 for expansion, 1 for final form]

5. Intersection: x24x+7=mx+3x^2 - 4x + 7 = mx + 3. x2(4+m)x+4=0x^2 - (4 + m)x + 4 = 0. For tangent, discriminant Δ=0\Delta = 0. ((4+m))24(1)(4)=0(-(4 + m))^2 - 4(1)(4) = 0. (4+m)216=0(4 + m)^2 - 16 = 0. (4+m)2=16(4 + m)^2 = 16. 4+m=±44 + m = \pm 4. m=0m = 0 or m=8m = -8. [4 marks: 1 for quadratic, 1 for Delta condition, 1 for solving, 1 for both values]

6. dydx=3x212\frac{dy}{dx} = 3x^2 - 12. Stationary points when dydx=03x2=12x2=4x=±2\frac{dy}{dx} = 0 \Rightarrow 3x^2 = 12 \Rightarrow x^2 = 4 \Rightarrow x = \pm 2. When x=2,y=824+5=11x = 2, y = 8 - 24 + 5 = -11. Point (2,11)(2, -11). When x=2,y=8+24+5=21x = -2, y = -8 + 24 + 5 = 21. Point (2,21)(-2, 21). d2ydx2=6x\frac{d^2y}{dx^2} = 6x. At x=2,d2ydx2=12>0x = 2, \frac{d^2y}{dx^2} = 12 > 0 \Rightarrow Minimum. At x=2,d2ydx2=12<0x = -2, \frac{d^2y}{dx^2} = -12 < 0 \Rightarrow Maximum. Coords: (2,11)(2, -11) [Min], (2,21)(-2, 21) [Max]. [4 marks: 1 for dy/dx, 1 for x values, 1 for coords, 1 for nature]

7. Midpoint of AB=(1+52,2+62)=(3,4)AB = (\frac{1+5}{2}, \frac{2+6}{2}) = (3, 4). Gradient of AB=6251=44=1AB = \frac{6-2}{5-1} = \frac{4}{4} = 1. Gradient of perpendicular bisector = 1-1. Equation: y4=1(x3)y=x+7y - 4 = -1(x - 3) \Rightarrow y = -x + 7 or x+y7=0x + y - 7 = 0. [3 marks: 1 for midpt, 1 for grad, 1 for eq]

8. 4x=x+34=x2+3xx2+3x4=0\frac{4}{x} = x + 3 \Rightarrow 4 = x^2 + 3x \Rightarrow x^2 + 3x - 4 = 0. (x+4)(x1)=0(x + 4)(x - 1) = 0. x=4x = -4 or x=1x = 1. If x=4,y=1x = -4, y = -1. Point P(4,1)P(-4, -1). If x=1,y=4x = 1, y = 4. Point Q(1,4)Q(1, 4). Coordinates: (4,1)(-4, -1) and (1,4)(1, 4). [3 marks: 1 for quadratic, 1 for x values, 1 for coords]

9. Since AOB=90\angle AOB = 90^\circ (axes are perpendicular), ABAB is the diameter. Centre is midpoint of ABAB. A(6,0),B(0,8)A(6,0), B(0,8). Midpoint = (6+02,0+82)=(3,4)(\frac{6+0}{2}, \frac{0+8}{2}) = **(3, 4)**. [2 marks: 1 for identifying diameter/midpoint logic, 1 for coords]

10. (a) 3x+12=4yy=34x+33x + 12 = 4y \Rightarrow y = \frac{3}{4}x + 3. Gradient = 34\frac{3}{4}. [1 mark] (b) Distance from (0,0)(0,0) to 3x4y+12=03x - 4y + 12 = 0. d=3(0)4(0)+1232+(4)2=1225=125=2.4d = \frac{|3(0) - 4(0) + 12|}{\sqrt{3^2 + (-4)^2}} = \frac{12}{\sqrt{25}} = \frac{12}{5} = **2.4**. [2 marks: 1 for formula/sub, 1 for answer]


Section B

11. (a) x2+2x3=0(x+3)(x1)=0x^2 + 2x - 3 = 0 \Rightarrow (x+3)(x-1)=0. x=3,1x = -3, 1. Coords: (3,0)(-3, 0) and (1,0)(1, 0). [2 marks] (b) y=(x+1)213=(x+1)24y = (x+1)^2 - 1 - 3 = (x+1)^2 - 4. Vertex: (1,4)(-1, -4). [2 marks] (c) Translation up 4 units: y=(x2+2x3)+4=x2+2x+1=(x+1)2y = (x^2 + 2x - 3) + 4 = x^2 + 2x + 1 = (x+1)^2. Equation: y=(x+1)2y = (x+1)^2. Vertex is (1,0)(-1, 0). Since min value is 0, it touches x-axis at one point. Does it intersect at two distinct points? No. [3 marks: 1 for eq, 1 for reasoning, 1 for conclusion]

12. (a) mAB=643(1)=24=12m_{AB} = \frac{6-4}{3-(-1)} = \frac{2}{4} = \frac{1}{2}. mBC=2653=42=2m_{BC} = \frac{2-6}{5-3} = \frac{-4}{2} = -2. Product mAB×mBC=12(2)=1m_{AB} \times m_{BC} = \frac{1}{2}(-2) = -1. Therefore ABBCAB \perp BC, so B=90\angle B = 90^\circ. [3 marks: 1 for m1, 1 for m2, 1 for product] (b) AB=42+22=20AB = \sqrt{4^2 + 2^2} = \sqrt{20}. BC=22+(4)2=20BC = \sqrt{2^2 + (-4)^2} = \sqrt{20}. Area = 12×20×20=10\frac{1}{2} \times \sqrt{20} \times \sqrt{20} = **10**. [2 marks] (c) Since right-angled at B, AC is diameter. Midpoint of AC = Centre = (1+52,4+22)=(2,3)(\frac{-1+5}{2}, \frac{4+2}{2}) = (2, 3). Radius squared r2=(2(1))2+(34)2=32+(1)2=10r^2 = (2 - (-1))^2 + (3 - 4)^2 = 3^2 + (-1)^2 = 10. Eq: (x2)2+(y3)2=10(x-2)^2 + (y-3)^2 = 10. x24x+4+y26y+9=10x^2 - 4x + 4 + y^2 - 6y + 9 = 10. x2+y24x6y+3=0x^2 + y^2 - 4x - 6y + 3 = 0. [3 marks: 1 for centre, 1 for r^2, 1 for eq]

13. (a) x26x+y2+8y=11x^2 - 6x + y^2 + 8y = 11. (x3)29+(y+4)216=11(x-3)^2 - 9 + (y+4)^2 - 16 = 11. (x3)2+(y+4)2=36(x-3)^2 + (y+4)^2 = 36. Centre: (3,4)(3, -4). Radius: 36=6\sqrt{36} = **6**. [3 marks: 1 for completing square, 1 for centre, 1 for radius] (b) Tangent is horizontal line y=ky=k. Distance from centre y-coord to line equals radius. k(4)=6|k - (-4)| = 6. k+4=6k=2k + 4 = 6 \Rightarrow k = 2. k+4=6k=10k + 4 = -6 \Rightarrow k = -10. Values: 2,102, -10. [3 marks: 1 for logic, 1 for each value]

14. (a) dydx=3x26x9\frac{dy}{dx} = 3x^2 - 6x - 9. 3(x22x3)=03(x3)(x+1)=03(x^2 - 2x - 3) = 0 \Rightarrow 3(x-3)(x+1) = 0. x=3,x=1x = 3, x = -1. [3 marks] (b) AA has x>0x > 0, so x=3x = 3. d2ydx2=6x6\frac{d^2y}{dx^2} = 6x - 6. At x=3,d2ydx2=186=12>0x = 3, \frac{d^2y}{dx^2} = 18 - 6 = 12 > 0. Nature: Minimum. [2 marks] (c) At x=1,y=139+10=1x = 1, y = 1 - 3 - 9 + 10 = -1. Point (1,1)(1, -1). Gradient m=3(1)26(1)9=12m = 3(1)^2 - 6(1) - 9 = -12. Eq: y(1)=12(x1)y+1=12x+12y - (-1) = -12(x - 1) \Rightarrow y + 1 = -12x + 12. y=12x+11y = -12x + 11. [3 marks: 1 for pt, 1 for grad, 1 for eq]

15. (a) m=1562=44=1m = \frac{1-5}{6-2} = \frac{-4}{4} = -1. y5=1(x2)y=x+7x+y7=0y - 5 = -1(x - 2) \Rightarrow y = -x + 7 \Rightarrow **x + y - 7 = 0**. [2 marks] (b) L2L_2 parallel m=1\Rightarrow m = -1. Passes (0,3)(0, -3). y=x3x+y+3=0y = -x - 3 \Rightarrow **x + y + 3 = 0**. [2 marks] (c) Midpoint PQ=(2+62,5+12)=(4,3)PQ = (\frac{2+6}{2}, \frac{5+1}{2}) = (4, 3). L3L1m=1L_3 \perp L_1 \Rightarrow m = 1. Eq L3:y3=1(x4)y=x1L_3: y - 3 = 1(x - 4) \Rightarrow y = x - 1. Intersection L2L_2 and L3L_3: x3=x12x=2x=1-x - 3 = x - 1 \Rightarrow 2x = -2 \Rightarrow x = -1. y=11=2y = -1 - 1 = -2. Coords: (1,2)(-1, -2). [4 marks: 1 for midpt, 1 for L3 eq, 1 for solving, 1 for coords]

16. Distance between centres d=(82)2+(33)2=6d = \sqrt{(8-2)^2 + (3-3)^2} = 6. (a) External touch: d=r1+r26=4+rr=2d = r_1 + r_2 \Rightarrow 6 = 4 + r \Rightarrow **r = 2. [2 marks] (b) Internal touch: d=r1r26=4rd = |r_1 - r_2| \Rightarrow 6 = |4 - r|. 4r=6r=24 - r = 6 \Rightarrow r = -2 (impossible). r4=6r=10r - 4 = 6 \Rightarrow **r = 10. [2 marks] (c) Intersect at 2 points: r1r2<d<r1+r2|r_1 - r_2| < d < r_1 + r_2. 42<d<4+22<d<6|4 - 2| < d < 4 + 2 \Rightarrow 2 < d < 6. Range: 2<d<62 < d < 6. [2 marks]

17. (a) Reflection in y-axis: replace xx with x-x. y=2(x)28(x)+5y=2x2+8x+5y = 2(-x)^2 - 8(-x) + 5 \Rightarrow **y = 2x^2 + 8x + 5**. [2 marks] (b) xvertex=b2a=84=2x_{vertex} = -\frac{b}{2a} = -\frac{8}{4} = -2. y=2(4)16+5=3y = 2(4) - 16 + 5 = -3. Coords: (2,3)(-2, -3). [2 marks] (c) Min value is -3. For 2 intersections, line must be above minimum. c>3c > -3. [2 marks]

18. (a) mAC=7131=62=3m_{AC} = \frac{7-1}{3-1} = \frac{6}{2} = **3**. [1 mark] (b) Altitude from B is AC\perp AC. Gradient =13= -\frac{1}{3}. Passes B(5,3)B(5,3). y3=13(x5)3y9=x+5x+3y14=0y - 3 = -\frac{1}{3}(x - 5) \Rightarrow 3y - 9 = -x + 5 \Rightarrow **x + 3y - 14 = 0**. [3 marks] (c) Eq of AC: y1=3(x1)y=3x2y - 1 = 3(x - 1) \Rightarrow y = 3x - 2. Sub into altitude eq: x+3(3x2)14=0x + 3(3x - 2) - 14 = 0. x+9x614=010x=20x=2x + 9x - 6 - 14 = 0 \Rightarrow 10x = 20 \Rightarrow x = 2. y=3(2)2=4y = 3(2) - 2 = 4. Coords: (2,4)(2, 4). [3 marks]

19. (a) Above x-axis \Rightarrow No real roots AND a>0a > 0. Δ<0k24(1)(9)<0k2<36\Delta < 0 \Rightarrow k^2 - 4(1)(9) < 0 \Rightarrow k^2 < 36. 6<k<6-6 < k < 6. [3 marks] (b) Intersection: x2+kx+9=2xx2+(k2)x+9=0x^2 + kx + 9 = 2x \Rightarrow x^2 + (k-2)x + 9 = 0. Two distinct points Δ>0\Rightarrow \Delta > 0. (k2)236>0(k-2)^2 - 36 > 0. (k2)2>36(k-2)^2 > 36. k2>6k - 2 > 6 or k2<6k - 2 < -6. k>8k > 8 or k<4k < -4. [3 marks]

20. (a) O(0,0),B(6,4)O(0,0), B(6,4). m=46=23m = \frac{4}{6} = \frac{2}{3}. Eq: y=23xy = \frac{2}{3}x or 2x3y=02x - 3y = 0. [1 mark] (b) A(6,0),C(0,4)A(6,0), C(0,4). m=4006=23m = \frac{4-0}{0-6} = -\frac{2}{3}. Eq: y=23x+42x+3y12=0y = -\frac{2}{3}x + 4 \Rightarrow **2x + 3y - 12 = 0**. [2 marks] (c) Diagonals of rectangle bisect each other. Midpoint of OB. (62,42)=(3,2)(\frac{6}{2}, \frac{4}{2}) = **(3, 2)**. [1 mark] (d) Centre (3,2)(3,2). Radius = dist from (3,2)(3,2) to (0,0)=9+4=13(0,0) = \sqrt{9+4} = \sqrt{13}. Eq: (x3)2+(y2)2=13(x-3)^2 + (y-2)^2 = 13. x26x+9+y24y+4=13x^2 - 6x + 9 + y^2 - 4y + 4 = 13. x2+y26x4y=0x^2 + y^2 - 6x - 4y = 0. [3 marks]