1. **State the problem:** We have a compound L-shaped figure made of two rectangles. The total area is 188 m². We need to find the value of $x$ given the side lengths in terms of $x$.
2. **Identify the rectangles:**
- Rectangle 1 (left vertical part): height = $4x + 3$, width = $2x + 2$
- Rectangle 2 (top right part): height = $3x$, width = $x - 2$
3. **Calculate the area of each rectangle:**
- Area of Rectangle 1 = height × width = $(4x + 3)(2x + 2)$
- Area of Rectangle 2 = height × width = $(3x)(x - 2)$
4. **Write the total area equation:**
$$
(4x + 3)(2x + 2) + 3x(x - 2) = 188
$$
5. **Expand the terms:**
$$
(4x)(2x) + (4x)(2) + 3(2x) + 3(2) + 3x^2 - 6x = 188
$$
$$
8x^2 + 8x + 6x + 6 + 3x^2 - 6x = 188
$$
6. **Simplify the expression:**
$$
8x^2 + 3x^2 + (8x + 6x - 6x) + 6 = 188
$$
$$
11x^2 + 8x + 6 = 188
$$
7. **Bring all terms to one side:**
$$
11x^2 + 8x + 6 - 188 = 0
$$
$$
11x^2 + 8x - 182 = 0
$$
8. **Solve the quadratic equation using the quadratic formula:**
$$
x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \quad \text{where } a=11, b=8, c=-182
$$
Calculate the discriminant:
$$
\Delta = 8^2 - 4 \times 11 \times (-182) = 64 + 8008 = 8072
$$
Calculate the roots:
$$
x = \frac{-8 \pm \sqrt{8072}}{22}
$$
$$
\sqrt{8072} \approx 89.82
$$
So,
$$
x_1 = \frac{-8 + 89.82}{22} = \frac{81.82}{22} \approx 3.719
$$
$$
x_2 = \frac{-8 - 89.82}{22} = \frac{-97.82}{22} \approx -4.446
$$
9. **Interpret the solution:** Since lengths must be positive, we discard $x_2$.
10. **Final answer:**
$$
\boxed{x = 3.72}
$$
(to 3 significant figures)
Compound Shape Area
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