If every side of a triangle is doubled, then the area of the new triangle increases by what percentage?

Answer: C. 300%

Answer: C) 300%
Explanation: If every side is doubled, the semi-perimeter doubles and each factor s, s - a, s - b, s - c doubles.
New area = √(16 × s(s - a)(s - b)(s - c)) = 4 × old area.
Increase = 4 - 1 = 3 times the original = 300%.

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