Difficulty: Medium
Correct Answer: √265cm
Explanation:
Introduction / Context:This problem uses two invariants of a right triangle—Pythagoras and area—to recover the legs, then applies specified changes to the legs and recomputes the hypotenuse.
Given Data / Assumptions:
Concept / Approach:From ab and a^2 + b^2, obtain (a + b)^2 = a^2 + b^2 + 2ab = 100 + 96 = 196 → a + b = 14. Solve a and b from t^2 − 14t + 48 = 0.
Step-by-Step Solution:
t^2 − 14t + 48 = 0 → (t − 6)(t − 8) = 0 → {a, b} = {6, 8}.Shorter = 6, longer = 8.New legs: 6/2 = 3 and 8*2 = 16.New hypotenuse = √(3^2 + 16^2) = √(9 + 256) = √265.Verification / Alternative check:Original: ab = 48 and a^2 + b^2 = 100 hold for 6 and 8. Transform as per instruction; recomputation matches √265 exactly.
Why Other Options Are Wrong:√245, √255, √275, √225 are not equal to √(3^2 + 16^2).
Common Pitfalls:Halving/doubling the wrong legs or attempting to scale the hypotenuse directly rather than recomputing with Pythagoras after the change.
Final Answer:√265cm
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