Math Question: In triangle ABC, angle A is bisected by a line segment that intersects BC at point D. If angle A measures 50 degrees, and angle B measures 80 degrees, find the measure of angle BCD.
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Question: Graph the inequality 3x + 4y ≤ 12 on a coordinate plane. Identify and shade all the valid solutions.
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What is the second derivative of the function f(x) = 5x^3 - 2x^2 + 7x - 4?