2. In RT △ ABC, ∠ c = 90, CM is the center line on the side of AB, and CD is the height on the side of AB. If cm = AC = 4, CD = _ _ _ _ _ _ _ _

3. If the waist length of an isosceles right triangle is 4㎝, then the high position on the hypotenuse is _ _ _ _ _ _ _.

4. In Rt△ABC, if hypotenuse AB = 25 ㎝ and right angle AC = 7 ㎝, then the face of triangle ABC is equal to _ _ _ _ _ _.

5. There are two points A(x, -2) B (2, -6) on the teaching coordinate plane. If the distance between two points A and B is 5, then the value of X is _ _ _ _ _ _ _.

6. As shown in the figure, if ∠ A = ∠ B = 90, ∠ 1 = 34, and CF = DF, then ∠2 is _ _ _ _ _ _.

7. As shown in the figure, in Rt△ABC, CD is the center line on the hypotenuse AB, and the area of equilateral△ △ACD is equal to 36√3, so the length of BC is _ _ _ _ _ _ _ _ _ _ _.

8. In △ABC, ∠ B = 60, AD⊥BC, and the vertical foot is D. If AD = 3 ㎝ and AC = 5 ㎝, then S △ ABC = _ _ _ _ _ \ \ \. .

9. As shown in the figure, in quadrilateral ABCD, AB = 12 ㎝, BC = 13 ㎝, CD = 4 ㎝, AD = 3 ㎝, D = 90, then S quadrilateral ABCD = _. .

The bisectors of ∠B and ∠C in 10 and △ABC intersect with point I, and the passing point I is DE‖BC, which intersects with AB and AC at D and E respectively. If AB = 8cm and AC = 6cm, then the circumference of △ADE is equal to _ _ _ _ _.