If the inscribed circle O of the triangle ABC and the tangent points of the three sides of the triangle are D, e and f respectively, then what is the center of the triangle def

RELATED INFORMATIONS

• 1. If the inscribed circle of triangle ABC and the tangent points of three sides are D, e and f respectively, the triangle def must be an acute triangle Why?
• 2. Circle O is the inscribed circle of triangle ABC, D, e and F are the tangent points. What are the characteristics of the shape of triangle def? Please explain the reasons
• 3. It is known that ⊙ o is the inscribed circle of △ ABC, and the tangent points are D, e and F. let ⊙ a = x, ⊙ EDF = y, and find the functional relationship between Y and X
• 4. As shown in the figure, △ ABC is an equilateral triangle, points D, e and F are on the sides of AB, BC and Ca respectively, and △ DEF is an equilateral triangle. Proof: △ ADF ≌ △ CFE
• 5. In triangle ABC is equilateral triangle, if angle Abe = angle BCF = angle CAD, is triangle def equilateral triangle? Why?
• 6. It is known that a (0,1) B (2,0) C (4,3) (1) finds the area of the triangle, and (2) sets the point P on the coordinate axis, and the triangle ABP corresponds to the area of the triangle ABC Finding the p-coordinate of a point Mainly (2) Talk about it
• 7. Known: a (0,1), B (2,0), C (4,3) (1) find the area of triangle ABC (2) point P on the coordinate axis, and triangle ABP and triangle ABC
• 8. Finding the inscribed circle of triangle ABC What about the vertical line from the center to the edge? It's a ruler. You can't use a scale. Only compasses and pens.
• 9. Please draw ABC's centrosymmetric figure about point d with ruler drawing method
• 10. Are isosceles triangles and equilateral triangles centrosymmetric?
• 11. As shown in the figure, triangle ABC is equal to triangle def. Angle a = 50 ° and angle e = 20 ° find angle B and angle def
• 12. In △ ABC, ∠ BAC: ∠ ACB: ∠ ABC = 4:3:2, and △ ABC ≌ △ def, then ∠ def=______ Degree
• 13. As shown in the figure, triangle ABC is equal to triangle def, angle a = angle D, angle B = angle e, ab = 3, BC = 4, triangle def perimeter is 9.5, point C is the midpoint of DF, find the length of CF
• 14. It is known that, as shown in the figure, ∠ ABC = ∠ DCB, BD and Ca are bisectors of ∠ ABC and ∠ DCB respectively
• 15. As shown in Fig. 12.1-6, △ ABC ≌ △ EBD is known, and it is verified that ∠ 1 = 2
• 16. As shown in the figure, let △ ABC and △ CDE be equilateral triangles, and ∠ EBD = 62 °, then the degree of ∠ AEB is () °
• 17. E. B and C are on the same straight line, Ba bisects ∠ EBD, ∠ DBC = 30 °. Calculate the degree of ∠ ABC
• 18. If point O is the outer center of triangle ABC and OA + ob + CO = 0, then what is the inner angle c,
• 19. (1) Given that point O is any point on the plane of equilateral triangle ABC, connect OA and extend to e such that AE = OA with OB.OC Make a parallelogram obfc for the adjacent edge and connect EF. Please explore the quantitative relationship between EF and BC. (2) Given that point O is any point on the plane of the isosceles right triangle ABC (BC is the hypotenuse), connect OA and extend to e, so that AE = OA. Take ob.oc as the adjacent side, make a parallelogram obfc, connect EF. Then the quantitative relationship between EF and BC is () (3) given that point O is any point on the plane of right triangle ABC (BC is the hypotenuse), connect OA and extend it to e, so that AE = OA, and connect EF with OB and OC as parallelogram obfc. Please explore the quantitative relationship between EF and BC.
• 20. Given that point O is any point in equilateral triangle ABC, connect OA and extend to e, so that AE = OA Taking OB and OC as adjacent sides, make parallelogram obfc and connect EF BC.EF= Root 3bC