It is known that in △ ABC, D is any point on the edge of ab Please write down the steps clearly

According to the triangle trilateral relation theorem, AD + AC > DC is obtained, and ab AC > DB DC is obtained by adding BD on both sides

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1. As shown in the figure, in △ ABC, ab = AC, ∠ BAC = 36 °, CD bisection ∠ ACB intersects AB at point D, AE parallels DC intersects BC extension line at point E, if DB = 2, CD = 3, AE = how much?
2. As shown in the figure, given that point F is a point on the extension line of the edge BC of △ ABC, DF ⊥ AB is at D, intersection AC is at e, and ∠ a = 56 °, f = 31 °, calculate the degree of ∠ ACB
3. As shown in the figure, given that point E is on the edge ab of △ ABC, point D is on the extension line of Ca, and point F is on the extension line of BC, what is the size relationship between ∠ ACF and ∠ D? Please give reasons
4. As shown in the figure, △ ABC, ab = AC, ∠ BAC = 110 °, ad is the middle line on the side of BC, and BD = be, then ∠ AED degree is______ ．
5. Triangle ABC is an equilateral triangle, D is the midpoint of side AB, de and BC are perpendicular, and the area of triangle BDE is 5 square centimeters. Find the area of triangle ABC
6. Triangle ABC and triangle BDE are equilateral triangles. This paper proves that: (1) triangle ABC is equal to triangle CBD (2) AE = De Please, hurry up
7. As shown in the figure, in △ ABC, CF ⊥ AB is in F, be ⊥ AC is in E, M is the midpoint of BC, EF = 5, BC = 8, then the perimeter of △ EFM is______ ．
8. As shown in the figure, in △ ABC, CF ⊥ AB is in F, be ⊥ AC is in E, M is the midpoint of BC, EF = 5, BC = 8, then the perimeter of △ EFM is______ ．
9. In triangle ABC, CF is perpendicular to AB and be is perpendicular to AC and E. m is the midpoint of BC, BF = 5 and BC = 8. Can you determine the perimeter of triangle EFM?
10. As shown in the figure, in △ ABC, ab = AC, D, e and F are on three sides respectively, and be = CD, BD = CF, G is the midpoint of EF
11. It is known that △ ABC, ad bisects ∠ BAC and intersects BC with D, DB = DC. Prove that △ ABC is an isosceles triangle. Prove that: ∵ DB = DC ∵ ad is the middle line of △ ABC ∵ ad bisects ∠ BAC and intersects BC with D ∵ ad is also the angle bisector of ∠ BAC in △ ABC. Is ∵ ABC an isosceles triangle?
12. As shown in the figure, in △ ABC, ∠ C = 90 °, ad is the bisector of ∠ BAC, de ⊥ AB is on e, f is on AC, DB = DF As shown in the figure, in △ ABC, ∠ C = 90 °, ad is the bisector of ∠ BAC, de ⊥ AB is on e, f is on AC, DB = DF
13. As shown in the figure, AC ⊥ CB, BD ⊥ CB, ab = DC, verify ∠ abd = ∠ ACD
14. As shown in the figure, given AB = AC, DB = DC, try to explain ∠ abd = ∠ ACD
15. Known: as shown in the figure, ab = AC, ∠ abd = ∠ ACD
16. As shown in the figure, ad bisects ∠ BAC, de ⊥ AB in E, DF ⊥ AC in F, and DB = DC, proving: EB = FC
17. As shown in the figure, ad bisects ∠ BAC, de ⊥ AB in E, DF ⊥ AC in F, and DB = DC, proving: EB = FC
18. As shown in the figure, ad bisects ∠ BAC, de ⊥ AB in E, DF ⊥ AC in F, and DB = DC, proving: EB = FC
19. As shown in the figure, Bo = OC, ab = DC, BF ‖ CE, and a, B, C, D are on the same line
20. Given that f (x) = - X & sup3; - x + 1, (x belongs to R), it is proved that y = f (x) is a decreasing function on the domain of definition, and there is at most one real value x satisfying the equation f (x) = 0