1. **Problem (a):** Calculate the dimensions of the smaller rectangle given that the area of the larger rectangle is 4 times the area of the smaller rectangle.
2. **Given:**
- Larger rectangle dimensions: height = 4 cm, width = 12 cm
- Smaller rectangle dimensions: height = $x$ cm, width = $x + 2$ cm
- Area of larger rectangle = 4 \times area of smaller rectangle
3. **Formula for area of rectangle:**
$$\text{Area} = \text{height} \times \text{width}$$
4. **Calculate areas:**
- Area of larger rectangle = $4 \times 12 = 48$ cm$^2$
- Area of smaller rectangle = $x \times (x + 2) = x(x + 2)$ cm$^2$
5. **Set up the equation:**
$$48 = 4 \times x(x + 2)$$
6. **Simplify the equation:**
$$48 = 4x^2 + 8x$$
7. **Divide both sides by 4:**
$$\cancel{4} \times 12 = \cancel{4}x^2 + 2x$$
$$12 = x^2 + 2x$$
8. **Rewrite as a quadratic equation:**
$$x^2 + 2x - 12 = 0$$
9. **Factor the quadratic:**
$$ (x + 4)(x - 3) = 0$$
10. **Solve for $x$:**
$$x + 4 = 0 \Rightarrow x = -4 \quad \text{(not valid since length cannot be negative)}$$
$$x - 3 = 0 \Rightarrow x = 3$$
11. **Dimensions of smaller rectangle:**
- Height = $3$ cm
- Width = $3 + 2 = 5$ cm
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12. **Problem (b):** Solve for $x$ in the equation:
$$\frac{2x - 3}{3} = \frac{x - 2}{5}$$
13. **Cross multiply:**
$$5(2x - 3) = 3(x - 2)$$
14. **Expand both sides:**
$$10x - 15 = 3x - 6$$
15. **Bring all terms to one side:**
$$10x - 3x = -6 + 15$$
$$7x = 9$$
16. **Solve for $x$:**
$$x = \frac{9}{7}$$
**Final answers:**
- (a) Smaller rectangle dimensions: height = 3 cm, width = 5 cm
- (b) $x = \frac{9}{7}$
Rectangle Dimensions D1Ff8B
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