How many ways can 5 different colored balls be arranged in a row?
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What is the length of the side opposite the 45° angle in a triangle with side lengths 9 and 13?
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Question: Find the vertex form of the quadratic function y = x² - 4x - 5. Graph the function, and determine the vertex, axis of symmetry, and y-intercept. Identify if the parabola opens upward or downward.