1. **Problem 1: Draw and reflect triangle ABC**
- Given vertices: A(-5,-2), B(-3,-4), C(-1,-2).
- Reflect triangle ABC in the line $y=0$ (the x-axis).
- Then reflect the image triangle A'B'C' in the y-axis.
2. **Reflection formulas:**
- Reflection in $y=0$: $(x,y) \to (x,-y)$.
- Reflection in y-axis: $(x,y) \to (-x,y)$.
3. **Reflect ABC in $y=0$:**
- $A(-5,-2) \to A'(-5,2)$
- $B(-3,-4) \to B'(-3,4)$
- $C(-1,-2) \to C'(-1,2)$
4. **Reflect A'B'C' in y-axis:**
- $A'(-5,2) \to A''(5,2)$
- $B'(-3,4) \to B''(3,4)$
- $C'(-1,2) \to C''(1,2)$ (correcting given $C''$ coordinates)
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5. **Problem 2: Enlargement scale factor and length**
- Given $AB=3$ cm, $A'B'=6$ cm.
- Scale factor $k = \frac{A'B'}{AB} = \frac{6}{3} = 2$.
6. **Find $B'C'$ given $BC=4.5$ cm:**
- $B'C' = k \times BC = 2 \times 4.5 = 9$ cm.
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7. **Problem 3: Area scale factor of enlargement**
- Original area = 4 cm$^2$, image area = 64 cm$^2$.
- Area scale factor $= \frac{\text{image area}}{\text{original area}} = \frac{64}{4} = 16$.
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8. **Problem 4: Transformation of points P, A, B, C, O**
- Given points and images:
- $P(2,3) \to P'(y,x) = (3,2)$
- $A(4,3) \to A'(3,4)$
- $B(4,4) \to B'(4,4)$
- $C(6,4) \to C'(4,6)$
- $O(7,2) \to O'(2,7)$
9. **Describe transformation:**
- The transformation swaps coordinates: $(x,y) \to (y,x)$.
- This is a reflection in the line $y=x$.
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10. **Problem 5: Enlargement of triangle P**
- Given scale factors from ratios:
- $k = \frac{A'B'}{AB} = \frac{2.5}{1.2} = \frac{25}{12} \approx 2.08$
- $k = \frac{B'C'}{BC} = \frac{12}{5} = 2.4$
- These differ slightly; likely approximate or measurement error.
- The centre of enlargement is the point where lines joining corresponding vertices intersect (not given explicitly).
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11. **Problem 6: Enlargement of triangle ABC to A'B'C'**
- Given:
- $A(1,1), B(4,5), C(2,4)$
- $A'(2,0), B'(8,8), C'(4,6)$
12. **Check if A'B'C' is enlargement of ABC:**
- Calculate lengths:
- $AB = \sqrt{(4-1)^2 + (5-1)^2} = \sqrt{9 + 16} = 5$
- $A'B' = \sqrt{(8-2)^2 + (8-0)^2} = \sqrt{36 + 64} = 10$
- Scale factor $k = \frac{A'B'}{AB} = \frac{10}{5} = 2$.
13. **Centre of enlargement:**
- Draw lines $AA'$, $BB'$, $CC'$ and find their intersection.
- Using coordinates, solve equations of lines:
- $AA'$ passes through $(1,1)$ and $(2,0)$
- $BB'$ passes through $(4,5)$ and $(8,8)$
- $CC'$ passes through $(2,4)$ and $(4,6)$
- Intersection point is centre of enlargement.
14. **Calculate centre:**
- Line $AA'$ slope: $m = \frac{0-1}{2-1} = -1$; equation: $y-1 = -1(x-1) \Rightarrow y = -x + 2$
- Line $BB'$ slope: $m = \frac{8-5}{8-4} = \frac{3}{4}$; equation: $y-5 = \frac{3}{4}(x-4) \Rightarrow y = \frac{3}{4}x + 2$
- Solve for intersection:
$$-x + 2 = \frac{3}{4}x + 2$$
$$-x = \frac{3}{4}x$$
$$-x - \frac{3}{4}x = 0$$
$$-\frac{7}{4}x = 0 \Rightarrow x=0$$
- Substitute $x=0$ into $y = -x + 2$: $y=2$
- Centre of enlargement is $(0,2)$.
15. **Scale factor confirmed as 2.**
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16. **Problem 7: Construct image of triangle ABC under enlargement centre (0,0) and factor $-\frac{1}{2}$**
- Given points $A(1,1), B(3,3), C(2,2.5)$.
- Enlargement formula: $(x,y) \to (k x, k y)$ with $k = -\frac{1}{2}$.
17. **Calculate images:**
- $A' = (1 \times -\frac{1}{2}, 1 \times -\frac{1}{2}) = (-0.5, -0.5)$
- $B' = (3 \times -\frac{1}{2}, 3 \times -\frac{1}{2}) = (-1.5, -1.5)$
- $C' = (2 \times -\frac{1}{2}, 2.5 \times -\frac{1}{2}) = (-1, -1.25)$
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18. **Problem 8: Translation of triangle ABC by $T=(-2,3)$**
- Given points $A(1,1), B(3,3), C(2,2.5)$.
- Translation formula: $(x,y) \to (x + t_x, y + t_y)$ with $t_x = -2$, $t_y = 3$.
19. **Calculate images:**
- $A' = (1 - 2, 1 + 3) = (-1, 4)$
- $B' = (3 - 2, 3 + 3) = (1, 6)$
- $C' = (2 - 2, 2.5 + 3) = (0, 5.5)$
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**Final answers:**
- Reflected points $A''(5,2), B''(3,4), C''(1,2)$.
- Scale factor of enlargement $k=2$.
- Length $B'C' = 9$ cm.
- Area scale factor $=16$.
- Transformation $(x,y) \to (y,x)$ is reflection in $y=x$.
- Centre of enlargement for ABC to A'B'C' is $(0,2)$.
- Enlargement image points with factor $-\frac{1}{2}$: $A'(-0.5,-0.5), B'(-1.5,-1.5), C'(-1,-1.25)$.
- Translation image points: $A'(-1,4), B'(1,6), C'(0,5.5)$.
Triangle Transformations 40B8C1
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