As shown in the figure, the quadrilateral ABCD is a square, △ ADF is rotated to get △ Abe, ∠ 1 = ∠ 2, please judge: (1) the shape of △ AEG; (2) the relationship between Ag and BG + DF
(1) From the properties of rotation, it can be concluded that ∠ EAB = ∠ 1 = ∠ 2, ∠ EAF = 90 °, EB = DF, ∠ EAG = 90 °- ∠ 2, then ∠ e = 90 °- ∠ EAB = 90 °- ∠ 2, ∠ EAG = ∠ e, △ AEG is isosceles triangle; (2) from (1) we can get: EB = DF, then Ag = eg = EB + BG = BG + DF
RELATED INFORMATIONS
- 1. If AF = 4, ab = 7, find: (1) point out the rotation center and rotation angle; (2) find the length of de; (3) what is the position relationship between be and DF? And explain the reason
- 2. The square ABCD and aefg common point a point Ge rotates aefg on ADAB, whether DF and BF are equal or not, it is incorrect to give a counter example Point G is on ad, point E is on AB, connect DF and BF, rotate square aefg around point a, whether DF and BF are still equal, incorrect, give a counterexample
- 3. As shown in the figure, in the square ABCD, e is the midpoint of AD, f is on CD, and DF = 1 / 4CD BE.EF.BF To prove that be is perpendicular to ef
- 4. As shown in the figure, rotate square ABCD around point a clockwise to get square aefg, edge FG and BC intersect at point h. verification: Hg = Hb
- 5. As shown in the figure, rotate square ABCD around point a clockwise to get square aefg, edge FG and BC intersect at point h. verification: Hg = Hb
- 6. Rotate square ABCD around point a clockwise to get square aefg. Edge FG and BC intersect at point H (as shown in the figure). Is segment Hg equal to segment HB? Please observe the conjecture first, and then prove your conjecture
- 7. If the side length of the square is 2cm and the area of the overlapping part (quadrilateral abhg) is 3 / 4 times the root sign 3, what is the rotation angle
- 8. After the square ABCD rotates n degrees around point a, the square aefg, EF and CD intersect at point o.1. Connect de and Ao, and prove that De is perpendicular to AO 2. If the side length of the square is 2 and the area of the overlapping part (quadrilateral aeod) is 4 / 3 times the root sign 3, the rotation angle n is calculated Baidu knows that there is a solution to this problem, but it uses trigonometric function Here we need to use quadrilateral or Pythagorean theorem to solve
- 9. As shown in the figure, rotate square ABCD around point a clockwise to get square aefg, edge FG and BC intersect at point h. verification: Hg = Hb
- 10. Let the side length of the square ABCD be 6, and rotate 30 degrees clockwise around point a to get the square aefg, where the side FG and BC intersect at h, and find the length of BH
- 11. As shown in the figure, ABCD is a square with side length of 2a, Pb ⊥ plane ABCD, Ma ∥ Pb, and Pb = 2mA = 2A, e is the midpoint of PD Verification: me ‖ plane ABCD Solution: cosine value of dihedral angle formed by plane PMD and plane ABCD Can you write me the specific process of the first question? I really don't understand. Please
- 12. In the geometry shown in the figure, the quadrilateral ABCD is a square, Ma ⊥ plane ABCD, PD ∥ Ma, e, G, f are the midpoint of MB, Pb, PC respectively, and ad = PD = 2mA. (I) verification: plane EFG ⊥ plane PDC; (II) calculation of the volume ratio of triangular pyramid p-mab and quadrangular pyramid p-abcd
- 13. As shown in the figure, the quadrilateral ABCD, cdef and efgh are all square. (1) is △ ACF similar to △ GCA? Talk about your reasons; (2) find the degree of ∠ 1 + 2
- 14. As shown in the figure, the quadrilateral ABCD, cdef and efgh are all square. (1) is △ ACF similar to △ GCA? Talk about your reasons; (2) find the degree of ∠ 1 + 2
- 15. Quadrilateral ABCD, cdef, efgh are square, connect AC, AF, Ag, calculate the degree of angle AFB + angle AGB, thank you
- 16. As shown in the figure, the quadrilateral ABCD, cdef and efgh are all square. (1) is △ ACF similar to △ GCA? Talk about your reasons; (2) find the degree of ∠ 1 + 2
- 17. As shown in the figure, the quadrilateral ABCD, cdef and efgh are all square. (1) is △ ACF similar to △ GCA? Talk about your reasons; (2) find the degree of ∠ 1 + 2
- 18. Known: as shown in the figure, in the quadrilateral ABCD, ad ‖ BC, BD bisects AC vertically
- 19. The quadrilateral ABCD and the quadrilateral aefg are both rhombic. The point E is on the ad side and the point G is on the extension line of the Ba side As shown in Figure 1, BD and CE are their diagonals. The extension line of Ge intersects BD at point Q and DC at point M. verify: GM ⊥ BD
- 20. As shown in the figure, the quadrilateral ABCD and aefg are both rhombic, in which point C is on AF, and points E and G are on BC and CD, respectively. If the angle bad = 135 degrees,