It is known that ad is the angular bisector of △ ABC, de ∥ AC intersects AB at point E, DF ∥ AB intersects AC at point F

RELATED INFORMATIONS

• 1. As shown in the figure, in △ ABC, ad is the height of BC, AE is divided equally into ∠ BAC, ∠ B = 75, ∠ C = 45, and ∠ Daewoo and ∠ AEC are calculated
• 2. In △ ABC, a-c = 90 ° AE is the bisector of BAC, and the degree of AEC is calculated
• 3. In △ ABC, ∠ BAC = 90 °, BD bisection ∠ ABC, AE ⊥ BC in E. verification: AF = ad
• 4. In △ ABC, ∠ BAC = 90 °, BD bisection ∠ ABC, AE ⊥ BC in E. verification: AF = ad
• 5. In triangle ABC, ad is high, be is middle line, angle CBE = 30 degrees, prove: ad = be
• 6. It is known that be is the middle line ad ⊥ BC in △ ABC, and it is shown that ad = be
• 7. In △ ABC, be is the middle line, ad ⊥ BC is in D, ∠ CBE = 30 °, please prove: ad = be The figure can be drawn according to the title. There are three sides of the triangle, one middle line and one high line. There are five sides in total
• 8. As shown in the figure, points a, B, D and E are on ⊙ o, and the extension lines of strings AE and BD intersect at point C. If AB is the diameter of ⊙ o, D is the midpoint of BC. Try to judge the size relationship between AB and AC, and give the proof Under the above conditions, what other conditions do △ ABC need to satisfy, and point e must be the midpoint of AC?
• 9. As shown in the figure, the tangent line AC passing through a point a on ⊙ O and the extension line of diameter BD of ⊙ o intersect at point C, and AE ⊥ BC passing through a intersects at point E. (1) prove: ∠ CAE = 2 ∠ B; (2) know: AC = 8 and CD = 4, find the radius of ⊙ O and the length of AE
• 10. As shown in the figure, BD is the diameter of circle O, e is a point on circle O, the straight line AE intersects the extension line of BD at point a, BC ⊥ AE at point C, and ∠ CBE = ∠ DBE. (1) try to explain that AC is the tangent line of circle O. (2) if the radius of circle O is 2, AE = 4, root 2, find the length of de
• 11. It is known that ad is the angular bisector of △ ABC, de ∥ AC intersects AB at point E, DF ∥ AB intersects AC at point F
• 12. It is known that, as shown in the figure, ad is the angular bisector of △ ABC, and EF bisectors ad vertically, intersecting AB and AC at e and f respectively
• 13. As shown in the figure, in RT △ ABC, ∠ B = 90 °, a = 30 ° and AC = 3, bend BC toward Ba, so that point C falls on point C 'on Ba, and the crease is be, then the length of C' e is___ ．
• 14. As shown in the figure, in △ ABC, point P moves from point B along the Ba edge to point a at a speed of 1cm / s, and point Q also moves from point B along the BC edge to point C at a speed of 2cm / s. After a few seconds, the area of △ PBQ is 36cm2?
• 15. As shown in the figure, in the RT triangle ABC, ∠ C = 90, AC = 6cm, BC = 8cm, points E and f start from two points a and B at the same time and move to points c and B along the direction of AC and Ba respectively The velocity of point E is 2cm / s, and that of point F is 1cm / s. if one of the points reaches the position, both points stop moving (1) Q. after a few seconds, the area of the triangle AEF is 16 / 5 (2) After a few seconds, EF bisects the perimeter of the RT triangle (3) Is there a line EF that bisects the perimeter and area of rtabc at the same time? If so, calculate the length of AE. If not, explain the reason
• 16. As shown in the figure, in the RT triangle ABC & nbsp;, the angle c = 90 °, AC = 3, BC = 4, a straight line & nbsp; l intersects with the edge BC and Ba and points & nbsp; E and f respectively, and the area of the divided triangle ABC & nbsp; is two equal parts, then the minimum length of the segment EF & nbsp; is______ ．
• 17. As shown in the figure, in RT △ ABC, ∠ ABC is a right angle, ab = 3, BC = 4, P is the moving point on the edge of BC, let BP = x, if we can find a point Q on the edge of AC, so that ∠ BQP = 90 °, then the value range of X is______ ．
• 18. 1. As shown in the figure: in the RT triangle ABC, the angle ABC = 90, Ba = BC. Point D is the midpoint of AB, CD, through point B as BC, vertical CD 1. As shown in the figure: in the RT triangle ABC, the angle ABC = 90, Ba = BC. Point D is the midpoint of AB, CD, passing through point B, BC is the vertical CD, intersecting CD and Ca at points E and f respectively. The straight line passing through point a and perpendicular to AB intersects at point G, connecting DF. The following four conclusions are given: (1) Ag ratio AB = FG ratio FB; (2) point F is the midpoint of Ge; (3) AF = 3 molecular root 2Ab; (4) s triangle ABC = 5S triangle BDF, The correct conclusion is as follows There are specific solutions
• 19. As shown in the figure, in △ ABC, ad ⊥ BC is at point D, AE bisects ⊥ BAC intersects BC at e, ⊥ C = 70 ° and ⊥ B = 38 ° to find the degree of ⊥ DAE
• 20. It is known as follows: as shown in the figure, in △ ABC, ad is the height on the edge of BC, AE is the bisector of ∠ BAC, ∠ B = 50 °, DAE = 10 °, (1) find the degree of ∠ BAE; (2) find the degree of ∠ C