Set 10: Linear Equations (Advanced)

Choice B is correct. Choice B is the correct answer. 1. Define: $W=w, L=2 w$. 2. Perimeter: $2(w + 2 w) = 60 \rightarrow 6 w = 60 \rightarrow w = 10$. 3. Length: $20$. 4. Area: $10\times 20 = 200$. Choice D is incorrect because it results from an error in the solution process. Choice A is incorrect because it results from an error in the solution process. Choice C is incorrect because it results from an error in the solution process.