Set 1: Linear Equations (Intermediate)

Choice D is correct. Choice D is the correct answer. 1. Define: Length = $l$, Width = $0.5l$. 2. Perimeter: $2l + 2(0.5 l) = 30$ 3. Simplify: $2l + l = 30 \rightarrow 3 l = 30$ 4. Divide by 3: $l = 10$ 5. Verify: Width 5. $20+ 10 = 30$ ✓ Choice C is incorrect because this is the width. Choice A is incorrect because it results from an error in the solution process. Choice B is incorrect because it results from an error in the solution process.