Difficulty: Easy
Correct Answer: 13 cm
Explanation:
Introduction / Context:
Questions on parallelograms typically use the direct formula Area = base * height. When one dimension is a multiple of the other, the unknown can be found using a single algebraic equation.
Given Data / Assumptions:
Concept / Approach:
Let height = h. Then base = 2h. Area formula becomes 2h * h = 2h^2. Solve for h from 2h^2 = 338.
Step-by-Step Solution:
Verification / Alternative check:
Base = 2 * 13 = 26 cm; Area check: 26 * 13 = 338 sq cm ✔️
Why Other Options Are Wrong:
14 cm ⇒ area 28*14 = 392 (too high); 16 cm ⇒ 32*16 = 512; 12 cm ⇒ 24*12 = 288; 'None' is unnecessary as an exact match exists.
Common Pitfalls:
Confusing base with height or using perimeter ideas instead of area; forgetting that only the positive root is physically meaningful.
Final Answer:
13 cm
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