In the right triangle ABC, CD is the middle line on the hypotenuse ab. given ∠ B = 30 ° and AC = 5cm, then AB and CD are equal to 3Q

Sin30 * AB = AC. so AB = 10, because D is the midpoint of AB, so ad = 1 / 2Ab = 5. So ACD is an congruent triangle, so CD = 5

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