As shown in the figure, fold the triangle paper ABC along de. when point a falls on the inner A1 of the quadrilateral BCDE, if ∠ 1 = 50 °∠ 2 = 20 °, calculate the degree of ∠ A1

I don't know if your figure is like this, ∠ 1, ∠ 2 are like this. It's estimated that the answer is almost as follows: after folding along De, △ ade ≌ △ A & # 39; de ≌} 3 = ∠ 4 & nbsp; & nbsp; → & nbsp; & nbsp;} 3 = (180 ° - 2) △ 2 = (180 ° - 20 °) △ 2 = 80 ° & nbsp;} 5 = ∠ 6 & nbsp; & nbsp

RELATED INFORMATIONS

1. As shown in the figure, fold the paper triangle ABC along de. when point a falls inside the quadrilateral BCDE, what is the relationship between angle A and angle 1 plus angle 2? Explain the reason
2. As shown in the figure, fold the triangle ABC paper along De, when point a falls inside the quadrilateral BCDE, ∠ a, ∠ 1, ∠ 2 When point a falls in the interior of the quadrilateral BCDE, what is the quantitative relationship among the degrees of ﹥ a, ﹥ 1, ﹥ 2? Please write it down and explain why
3. As shown in Figure 8, fold triangle ABC along De, when point a falls inside the quadrilateral BCDE As shown in the figure, when the triangle paper ABC is folded along De, when point a falls inside the quadrilateral BCDE, there is a quantitative relationship between a and ∠ 1 ＋ 2, which always remains unchanged. Please find out this rule? And write down the reasons
4. In the acute triangle ABC, ah is high, if AB + BH = HC, prove: angle B = 2, angle c (to process,) In the acute triangle ABC, ah is high, if AB + BH = HC, prove: angle B = 2, angle C
5. In triangle ABC, CD is the angular bisector, CF is the outer angular bisector, DF is parallel, BC intersects AC and E, CF intersects F, and de = EF is proved
6. It is known that the area of triangle ABC is 42.3 square centimeters, which is six times of the area of triangle EFB, and the area of parallelogram efcd
7. As shown in the figure, in RT △ D is the midpoint of the hypotenuse AB, f is the midpoint of AC, EF ‖ DC, intersects the extension line of BC at point E, and proves that the quadrilateral befd is isosceles trapezoid
8. It is known that in RT triangle ABC, D is the midpoint of hypotenuse AB, de / / BC, EF / / DC
9. In the triangle ABC, extend AC to point F so that CF = 2 / 1Ac, D and E are the midpoint of edge AB and BC respectively. Prove DC = EF
10. It is known that x = 2, y = 1 is the solution of the binary linear equations ax + by = 7, ax by = 1 about x.y=————
11. As shown in the figure, fold the paper △ ABC along De, point a falls at a ′, ∠ 1 + ∠ 2 = 150 °, then ∠ a=______ ．
12. As shown in the figure, when the triangle ABC paper is folded along De, and point a falls inside the quadrilateral BCDE, the quantitative relationship between ∠ A and ∠ 1 + 2 is
13. As shown in the figure, ABC, AB are equal to 10 cm, BC is equal to 7 cm, AC is equal to 6 cm. Fold the triangle along the straight line passing through point B so that point C falls at point E on the edge of AB, and the crease is BD. calculate the perimeter of the triangle AED
14. As shown in the figure, the triangle paper ABC, ab = 10cm, BC = 7cm, AC = 6cm, fold the triangle along the straight line passing through point B, so that the vertex C falls at point E on the edge of AB, and the crease is BD, then the perimeter of △ AED is______ cm．
15. As shown in the figure, D is a point on the edge AC of △ ABC, ed parallel BC intersects AB at point E, DF parallel AB intersects BC at point F, AE = one third AB, if the area of △ AED is 2, calculate the area of △ DFC
16. To seek for the combination of 1998 + 1999 + 2000 + 2001 +. + 2006 + 2007 + 2008
17. X-4x + 2Y + 2Y + 9 / 2 = 0, find XY
18. How much is 4x ^ 2Y · (- XY ^ 2) / x ^ 2Y ^ 4? It's better to have a process. Thank you~~ How much is (3x + 2) (x-3) - 3 (X-2) ^ 2?
19. Junior high school mathematics known (4x-2y-1) + root XY-2 = 0, find the value of 4x ^ 2y-4x ^ 2Y ^ 2 + XY ^ 2
20. Factorization 3x ^ 4 + x ^ 2y-2y ^ 2