What is the criterion of proving two triangles congruent based on the measurements of their corresponding sides and the included angles?
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Question: In a right triangle, if the length of the adjacent side is 10 units and the measure of the angle is 30 degrees, what is the length of the opposite side?
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What is the projection of vector a = (3, -4) onto the unit vector u = (2/√5, 1/√5)?