In △ ABC, AE bisection ∠ BAC intersects BC with E, de ‖ AC intersects AB with D, and DF ‖ BC intersects AC with F

It is proved that: as shown in the figure, ∵ AE bisection ∵ BAC intersects BC with E, ∵ de ∥ AC, ∵ de ∥ 2 = ∥ 3, ∵ 1 = ∥ 3, ∵ ad = de. and ∵ de ∥ AC, DF ∥ BC,

RELATED INFORMATIONS

1. In △ ABC, ab = AC, ad = 2, ad is the middle line of △ ABC, AE is the angular bisector of ∠ bad, DF ‖ AB intersects the extension of AE at point F, and the length of DF is calculated
2. In the triangle ABC, ab = 13, AC = 15, BC = 14!
3. As shown in the figure, D is a point on the edge BC of △ ABC. Given AB = 13, ad = 12, AC = 15, BD = 5, then the length of BC is______ ．
4. In the triangle ABC, AB equals 5, AC equals 7, ad is the middle line on the side of BC, then the range of ad is?
5. In the triangle ABC, ad is the middle line on the side of BC, AB is equal to 6, ad is equal to 5, AC is equal to 8 It's urgent!
6. In the triangle ABC, AB equals 20, AC equals 12, D is the middle line, and ad equals 8, find the length of BC
7. In △ ABC, ab = AC, ad is the midline on the side of BC, if AB = 17, BC = 16, then ad =?
8. As shown in the figure: in △ ABC, ∠ B = 90 °, ab = BD, ad = CD, calculate the degree of ∠ CAD
9. In △ ABC, ∠ BAC = 90 °, BD bisection ∠ ABC, AE ⊥ BC in E. verification: AF = ad
10. As shown in Figure 10, AD / / BC, ad = 5 cm, the area of triangle abd is 10 square cm, what is the height of ad side of triangle ACD
11. In the triangle ABC, the angles C = 90 °, D and E are the points on AB and AC respectively. Ad times AB = AE times AC, it is proved that ED is perpendicular to ab C: [documents and settings] administrator [desktop] unnamed.jpg
12. As shown in the figure, in the angle ABC, the angle c = 90 degrees, D and E are the points on AB and AC respectively, and ad · AB = AE · AC, then ed Is it perpendicular to ab? Please explain why
13. D. E are the points on the sides AB and AC of triangle ABC. Triangle ABC and triangle ade are similar triangles. If ad = 2cm, ab = 3cm, AC = 4cm, find the length of AE
14. The perimeter of △ ABC is 16. The end points of the three sides of △ ABC are connected to form a triangle, and then the midpoint of each side of the new triangle is connected to form a second triangle. And so on, the perimeter of the second triangle is 2006 power of A1 / 2 2007 power of B1 / 2 2008 power of C1 / 2 2009 power of D1 / 2
15. Given the point a (- 1, - 4), try to take a point B and C on the Y-axis and the line y = x to minimize the perimeter of the triangle ABC, and find the coordinates of B and C
16. Given the vertex a (1,4) of △ ABC, if point B is on the Y axis and point C is on the line y = x, then the minimum perimeter of △ ABC is______ ．
17. If the two vertex coordinates a (- 4,0), B (4,0) of △ ABC and the perimeter of △ ABC are 18, then the trajectory equation of vertex C is___ ．
18. (the third power of 4B / 7 - the square of 7ab + the square of 2B / 5) △ the square of 2B / 5
19. As shown in the figure, ad is the angular bisector of the outer angle of the triangle ABC. The intersection of AD and the circumscribed circle of the triangle ABC is at point D
20. As shown in the figure, it is known that ∠ B = ∠ C. If ad ‖ BC, does ad divide ∠ EAC equally? Please give reasons