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It is known that ad is the middle line of triangle ABC. Try to find the size of AB + AC and 2ad
A: ab + AC > 2ad
It is proved that extending ad makes de = ad, connecting be and CE
Because ad is the center line of triangle ABC
So BD = CD
Because ad = de
So the quadrilateral ABEC is a parallelogram
So AC = be
So in the triangle Abe
AB+BE>AE
That is ab + AC > 2ad
If the perimeter of a triangle is 10cm, one side is 3cm, and the other side is xcm, then the value range of X is
The perimeter of the triangle is 10cm, one side is 3cm, the other side is xcm, and the other side is 7-x
3+x>7-x,x>2
x-(7-x)
The base of isosceles triangle is 10cm long, and the value range of waist x is
∵2x＞10
∴x＞5
The range of waist x is x > 5cm
The length of two sides of a triangle is 8cm and 10cm respectively, and the length of the third side is xcm______ ．
In a ∵ triangle, the sum of any two sides is greater than the third side, ∵ x ﹤ 8 + 10 = 18, ∵ the difference of any two sides is less than the third side, ∵ x ﹥ 10-8 = 2, ∵ X's range is 2 ∵ x ﹤ 18
The lengths of two sides of a triangle are 7cm and 11cm respectively. What is the value range of its perimeter l?
Range of third side C: 11-7
If the base of isosceles triangle is 10cm long, the range of waist length is? Please explain and answer in detail
> 5 cm
If the waist length is x cm (x > 0), the sum of any two sides is greater than the third side
x＋x > 10…… (1)
10＋x > x…… (2)
x＋10 > x…… (3)
Where (2) and (3) are equivalent and hold for all real numbers
The solution (1) is: x > 5
If three sticks with the length of 4cm, 5cm and xcm form a triangle, then the value range of X is ()
The sum of any two sides of a triangle is greater than the third side, and the difference between any two sides of a triangle is less than the third side
So 5-4
If the base length of isosceles triangle is 5cm and the waist length is xcm, then the value range of X is
Any two sides of a triangle must be greater than the third side, and the inequality: x + x > 5 is obtained
∴x＞2.5
The perimeter of a parallelogram is 48CM, and the heights of the two parallelogram are 7cm and 5cm respectively. What is the area of the parallelogram
Let X and y be the two sides respectively, and then we get the system of linear equations of two variables
x+y=48/2
7x = 5Y (equal area)
Figure it out for yourself
It is known that the perimeter of the parallelogram is 68, and the heights of the two adjacent sides are 8 and 9 respectively
Let the long side be a and the short side be B. the system of equations can be formulated as follows
2（a+b）=68
8a=9b
The area of parallelogram is 144 square centimeter
RELATED INFORMATIONS
- 1. It is known that the perimeter of the parallelogram is 60cm, and the heights of the two adjacent sides are 8cm and 9cm respectively. The area of the parallelogram is calculated Try to be more detailed. I'm afraid I can't understand it, I have the wrong number. It's 68cm
- 2. If the height of the triangle is 4.8cm, the height of the parallelogram is（ If the height of the triangle is 4.8cm, the height of the parallelogram is（
- 3. The lengths of two adjacent sides of a parallelogram are 5cm and 8cm respectively. What is the perimeter of the parallelogram In addition to the above question -- It is known that a group of adjacent sides of a parallelogram are 5cm and 4cm respectively, and the height is 3cm. Then the perimeter of the parallelogram --?
- 4. [mathematics] if the area of a parallelogram is y cubic centimeter and its height on one side is 5 cm, then the length of this side is 5 cm___ cm. To prepare a certain pesticide, three kinds of raw materials (a, B and C) should be used. The mass ratio of the three raw materials is 5:3:9. If the mass of the raw material a is 5xkg, the mass of the prepared pesticide is 5__ Kilogram Solve the above two problems
- 5. It is known that the visual image of a square is a parallelogram, in which one side is 4 long, then the area of the square is () A. 16b. 64c. 16 or 64D. Cannot be determined
- 6. Proof: the sum of squares of the diagonals of a parallelogram is equal to twice the sum of squares of two adjacent sides
- 7. The two right sides of a right triangle are 6 and 8, and the three sides of a right triangle are the diameters of the three semicircles
- 8. It is known that three line segments are 10, 14 and 20 long respectively. Two of them are diagonals, and the other one can draw a parallelogram
- 9. The sum of two adjacent sides of a parallelogram is 15 cm. How many cm is the perimeter of the parallelogram? It's a list
- 10. When the absolute value pa-pb of a (2,0) B (- 1, - 3) P is the largest on the y-axis, the coordinate of point P is
- 11. If three line segments of length A-2, a + 5 and a + 2 are connected in turn to get a triangle, then the value range of a is () A. A ＞ - 1B. A ＞ 2C. A ＞ 5D
- 12. In the triangle ABC, if a [- 1,2,3], B [2, - 2,3], C [0.5,2.5,3], then the length of the central line CD on the side of ab
- 13. It is known that the circumference of a rectangle is 60cm, and the length is 20cm more than the width. Let the length of a rectangle be xcm and the width be YCM, and the binary linear equations about X and y are listed
- 14. As shown in figure 1-4-11, it is known that the perimeter of the quadrilateral ABCD is 25cm, and the distance between the opposite sides is de = 2cm and DF = 3cm respectively. Calculate the area (cm2) of the parallelogram
- 15. The base of a parallelogram is 8 cm, the height is half of the base, and the area of a triangle equal to its base and height
- 16. As shown in the figure, BD is the diagonal of parallelogram ABCD, AE ⊥ BD is in E, CF ⊥ BD is in F
- 17. In rectangle ABCD, e is the midpoint of BC, and AE ⊥ ed, if AE = 2, root 2, calculate the area of rectangle
- 18. If the circumference of the parallelogram ABCD is 50 cm and ab is 3 cm shorter than CD, then CD,
- 19. It is proved that the quadrilateral ABCD is a parallelogram
- 20. The edge length of rectangle ABCD is ab = 2, BC = 3, point P is a point on the edge of AD, q is any point on the edge of BC, connecting AQ, DQ, passing through point P as PE parallel DQ intersecting AQ at point E, PE parallel AQ intersecting DQ at point F. let the length of AP be x, try to find the functional relationship between the area of triangle PEF and X, and find out where the point P is, and what is the maximum area of triangle PEF? When the point q is where, the perimeter of the triangle ADQ is the smallest? (the process or method to determine where q is should be given, without proof)