Difficulty: Medium
Correct Answer: 6 cm
Explanation:
Introduction / Context:
This is a basic mensuration question about the area of a parallelogram. The formula is area = base * height. Since the base is related to the height (base = 2 * height), you substitute this relationship into the area formula and solve a simple quadratic equation for the height.
Given Data / Assumptions:
Concept / Approach:
Substitute b = 2h into A = b * h to get A = 2h^2. Solve for h using the given area value 72.
Step-by-Step Solution:
Verification / Alternative check:
If h = 6, then base b = 2 * 6 = 12. Area = 12 * 6 = 72 sq cm, exactly matching the given area. So the computed height is correct.
Why Other Options Are Wrong:
Common Pitfalls:
Students sometimes use the triangle area formula 1/2 * base * height by mistake. Another common error is taking h = 36 instead of sqrt(36). Always remember that h^2 = 36 implies h = 6, not 36.
Final Answer:
6 cm
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