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
(1) Reasons: let the side length of a square be a, AC = A2 + A2 = 2A, ∵ ACCF = 2AA = 2, CGAC = 2a2a = 2, ∵ ACCF = CGAC, ∵ - ACF = ∵ ACF, ∵ ACF ∽ GCA; (2) ∵ ACF ∽ GCA,
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- 1. 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
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- 8. 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
- 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
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- 12. 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
- 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
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