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)
(1) When C is on line AB,
MN = CM+CN = (1/2)(AC+BC) = (1/2)AB = 3 cm .
(2) When C is on the extension line of segment AB,
MN = CM-CN = (1/2)(AC-BC) = (1/2)AB = 3 cm .
RELATED INFORMATIONS
- 1. 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!
- 2. 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
- 3. 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
- 4. 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
- 5. 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
- 6. 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___
- 7. Line AB = 40mm, draw line BC = 16mm on line AB, D is the midpoint of AC, and find the length of CD
- 8. 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
- 9. 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
- 10. Given the relative vertices a (0, - 1) and C (2,5) of square ABCD, the coordinates of vertices B and D are obtained
- 11. 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.
- 12. 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
- 13. 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
- 14. 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
- 15. As shown in the figure, two points B and C divide the line ad into three parts of 2:3:4, e is the midpoint of the line ad, EC = 1.5cm, find the length of CD
- 16. As shown in the figure, in the trapezoidal ABCD, ab ‖ CD, e is the midpoint of AD, EF ‖ CB intersects AB at point F, if BC = 4cm, then the length of EF is______ cm.
- 17. As shown in the figure, point C is the midpoint of AB, D is the midpoint of CB, e is the midpoint of AD, ab = 12cm, find the length of CE
- 18. As shown in the figure, points a and B are on the straight line Mn, ab = 8cm, and the radii of ⊙ A and ⊙ B are 1cm ⊙ a moves from left to right at the speed of 2cm per second. At the same time, the radius of ⊙ B is also increasing. The relationship between the radius R (CM) and the time t (seconds) is r = 1 + T (t ≥ 0). (1) try to write the functional expression between the distance d between points a and B and the time t (seconds). (2) ask how many seconds after point a starts, the two circles are tangent
- 19. It is known that: as shown in Figure 1, M is a certain point on the fixed length line AB, C and D respectively start from m and B and move to the left along the straight line BA at the speed of 1cm / s and 3cm / s, and the direction of motion is shown by the arrow (C is on the line am, D is on the line BM) (1) If AB = 10cm, when points c and d move for 2S, find the value of AC + MD. (2) if points c and d move, there is always MD = 3aC, fill in the blank directly: am=______ Ab. (3) under the condition of (2), where n is a point on the line AB and an-bn = Mn, the value of mnab is obtained
- 20. As shown in the figure, B and C divide the line segment ad into three parts, the ratio is ab: BC: CD = 2:3:4, M is the midpoint of the line segment ad, CM = 1cm, find the length of the line segment AD and the value of CM: CD Don't copy it!