Difficulty: Medium
Correct Answer: 48
Explanation:
Introduction / Context:
This is an isosceles triangle with a given altitude to the base and a fixed perimeter. Using right-triangle relations after altitude splitting helps determine base and then area.
Given Data / Assumptions:
Concept / Approach:
The altitude to the base bisects the base: half-base = b/2. In the right triangle, a^2 = (b/2)^2 + 8^2. Perimeter: b + 2a = 32. Solve for b, then area = (1/2)*b*8.
Step-by-Step Solution:
Verification / Alternative check:
With b = 12, halves are 6; a = √(6^2 + 8^2) = √100 = 10; perimeter = 12 + 20 = 32 (checks).
Why Other Options Are Wrong:
50, 60, 70, 80 do not satisfy both the perimeter and altitude constraints; 48 is exact.
Common Pitfalls:
Assuming altitude equals median to equal sides; here it splits the base and creates two 6–8–10 right triangles.
Final Answer:
48
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