![](data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 72 71" width="72"></svg>)
In the isosceles triangle ABC, the vertical bisector of one waist AB intersects the other waist AC to F, the perpendicular foot is e, the perimeter of △ BFC is 20cm, ab = 12cm, Then the length of BC is___
AB = AC = 12cm, EF is the vertical bisector of AB, AF = BF,
BC = △ BFC perimeter - CF-BF = △ BFC perimeter - AC = 20-12 = 8cm
∴BC=8cm.
Given that point B is on line AC, AC = 20cm, M is the midpoint of AB and N is the midpoint of BC, find the length of line Mn
Answer with ∵ so ∵,
Because m is the midpoint of AB, then am = MB = AB / 2;
Similarly, if n is the midpoint of BC, then BN = NC = BC / 2
And because B is on the line AC, then AB + BC = AC = 20
So Mn = MB + BN = AB / 2 + BC / 2 = AC / 2 = 20 / 2 = 10
Point C is on line AB, m and N are the midpoint of line AC and BC respectively. If AB = 20cm, Mn =?
If you don't understand, then Mn = MC + CN = 1 / 2 (AC + CB) = 1 / 2Ab = 10cm
RELATED INFORMATIONS
- 1. Line AB = 40mm, draw line BC = 16mm on line AB, D is the midpoint of AC, and find the length of CD
- 2. Given that point C is a point on line AB, ab = 12cm, AC: BC = 1:3, and point m is the midpoint of line BC, find the length of line am
- 3. Given the line AB = 8cm, there is a point C on the line AB, and BC = 4cm, and the point m is the midpoint of the line AC, find the length of the line am
- 4. Given the relative vertices a (0, - 1) and C (2,5) of square ABCD, the coordinates of vertices B and D are obtained
- 5. It is known that the coordinates of three vertices of square ABCD are a (2,3) B (6,6) C (3,10), and the coordinates of point D can be obtained
- 6. It is known that: as shown in the figure, in trapezoidal ABCD, ad ‖ BC, BC = DC, CF bisects ∠ BCD, DF ‖ AB, and the extension line of BF intersects DC at point E
- 7. In the triangle ABC, 1. If ∠ C = 90, cosa = 12 / 13, find the value of SINB. 2. If ∠ a = 35, B = 65, try to compare the size of cosa and SINB If this triangle is an arbitrary acute triangle, can we judge the size of cosa + CoSb + COSC and Sina + SINB + sinc There is no graph
- 8. As shown in the figure, ab ⊥ BC, BC ⊥ CD, BF and CE are rays, and ∠ 1 = 2, try to explain BF ⊥ CE
- 9. There are four digits ABCD, and ABCD = (AB + CD) square, find all such four digits
- 10. In the trapezoid ABCD, ad ‖ BC, angle a = 90 °, ab = 7, ad = 2, BC = 3, whether there is a point P on the straight line AB, and find out the length of AP In the trapezoidal ABCD, ad ‖ BC, ∠ a = 90 °, ab = 7, ad = 2, BC = 3, ask whether there is a point P on the line AB, so that the triangle with P, a, D as the vertex is similar to the triangle with P, B, C as the vertex? If not, please explain the reason; if so, how many p points are there? And calculate the length of AP
- 11. It is known that point B is a point on the line AC, D is the midpoint of AC, e is the midpoint of AB, BC = 6. (1) draw a graph and find the length of de; (2) if (1) midpoint B is a point on the extension line of AC, other conditions remain unchanged, draw a graph and find the length of de
- 12. As shown in the figure, D is the midpoint of AC, DC = 2cm, BC = 1 / 2Ab, find the length of ab The picture shows: the middle part of a line segment (two endpoints: AC) is dB from left to right
- 13. As shown in the figure, point C is the point on line AB, and points D and E are the midpoint of line AC and BC respectively. If AC = 3cm and BC = 2cm, what is de? —·———·————·———————·————————·———— A D C E B
- 14. Given the line AB = 10, C is any point on the line AB, M is the midpoint of AC, n is the midpoint of BC, find the length of Mn No graph, standard process, all three solutions
- 15. Given that the line segment AB = CD and overlaps one third of each other, m and N are the midpoint of AB and CD respectively, and Mn = 14cm, find the length of ab Come on! There's no time!
- 16. As shown in the figure, there is an arbitrary point C on line AB, point m is the midpoint of line AC, and point n is the midpoint of line BC. When AB = 6cm, (1) find the length of line Mn. (3) (2) When C is on the extension line of AB and other conditions remain unchanged, find the length of the line segment Mn. (3 points)
- 17. If there are two points m and N on the line AB, point m divides AB into two parts of 1:2, point n divides AB into two parts of 2:1, and Mn = 4cm, then am=______ cm，BN=______ cm．
- 18. M is the midpoint of the line AB, n is a point on the line am, if Mn = 4, find the value of bn-an
- 19. It is known that there are two points m and N on the line ab. point m divides AB into two parts 2:3 and point n divides AB into two parts 4:1. If Mn = 3cm, the length of AM and Nb can be obtained
- 20. As shown in the figure, given that point C is the midpoint of line AB, D is any point on AC, m and N are the midpoint of AD and DB respectively, if AB = 16, find the length of Mn