Calculation of the first grade of junior high school 1.180 degrees - (48 degrees 39 minutes 40 seconds + 67 degrees 41 minutes 35 seconds) 109 degrees, 11 minutes, 4 seconds divided by 7 23 degrees 41 minutes 34 seconds times 3

Calculation of the first grade of junior high school 1.180 degrees - (48 degrees 39 minutes 40 seconds + 67 degrees 41 minutes 35 seconds) 109 degrees, 11 minutes, 4 seconds divided by 7 23 degrees 41 minutes 34 seconds times 3

1.180 degrees - (48 degrees 39 minutes 40 seconds + 67 degrees 41 minutes 35 seconds) 2.109 degrees 11 minutes 4 seconds divided by 73.23 degrees 41 minutes 34 seconds multiplied by 3 1.180 degrees - (48 degrees 39 minutes 40 seconds + 67 degrees 41 minutes 35 seconds) = 180 degrees - (115 degrees 80 minutes 75 seconds) = 180 degrees - (116 degrees 21 minutes 15 seconds) = 179 degrees 59 minutes 60 seconds - 116 degrees 21 minutes 15 seconds = 64 degrees 38 minutes 45

1. Starting from a vertex of a decagon, what is the number of triangles that divide a polygon into?
2. If a polygon has 14 diagonals, what is the number of sides of the polygon?
3. If the diagonal line passing through a vertex of a polygon is divided into eight triangles, what is the number of sides of the polygon?
4. Pentagon has () diagonals 5. Hexagon has () diagonals
6. Starting from a vertex of n-polygon (n > 3), we can draw () diagonal lines, which divide n-polygon into () triangles
7. If a polygon has 9 diagonals, then the number of sides of the polygon is ()
8. If the outer angle of a polygon is 40 degrees, then the number of sides of the regular polygon is ()
9. If the sum of inner angles of a polygon is twice the sum of outer angles, then the number of sides of the polygon is ()
10. The outer angle of a regular polygon cannot be equal to ()
11. If any inner angle of a regular polygon is equal to 120 °, then the leading diagonal from a vertex of the polygon is ()
12. If the sum of the exterior angles of a polygon is equal to 1 / 3 of the sum of its interior angles, then the number of sides of the polygon is ()
13. The degree of an inner angle of a regular octagon is ()
14. There are two regular polygons, the ratio of their sides is 1:2, and the ratio of their inner corners is 3:4. Can you confirm the number of their sides? Please explain the reason
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The n-polygon can be divided into (n-2) triangles 10-2 = 8 2 by crossing the same vertex of the n-polygon. From the n-polygon diagonal = n (n-3) / 2, n = 73, 8 + 2 = 10, 10 polygon. 4, 5 n-polygon diagonal = n (n-3) / 25, 9 n-polygon diagonal = n (n-3) / 27, one vertex can draw n-3 diagonal, which can be divided into

As shown in the figure, BD is divided into two parts, be is divided into ABC 2:5, DBE = 21 ° and the degree of ABC is calculated

Let ∠ Abe = 2x ° and get 2x + 21 = 5x-21. The solution is x = 14 and ﹥ ABC = 14 °× 7 = 98 °. The degree of ﹥ ABC is 98 degrees. So the answer is 98 degrees

In the expansion of (X-2 radical 2) ^ 8, what is the coefficient of x ^ 6?

In the expansion of (X-2 radical 2) ^ 8, the coefficient of x ^ 6 is C8 (2) * (- 2 √ 2) & sup2; = 224

There are 56 people in team a and 34 people in team B. after the two teams are transferred with the same number of people, team a is three times the number of team B,

Set up and transfer x people
According to the meaning of the title:
56-X=3*（34-X）
The solution is x = 23
It's 56. Oh, over

If x + y = 1, xy = - 1, find the value of x ^ 2 + y ^ 2
If x + y = 3, xy = 1, find the value of x ^ 2 + y ^ 2
If a + B = 3, ab = 2, find the value of (a-b) ^ 2
If A-B = 3, ab = 1, find a ^ 2 + B ^ 2 = - (a + b) ^ 2=------
I'm looking at two questions for you

x^2+y^2=(X+Y)^2-2XY=7
(a-b)^2=(a+b)^2-4ab=1
a^2+b^2=(a-b)^2+2ab=11
(a+b)^2=(a-b)^2+4ab=13

In order to organize a mixed doubles match from 5 male and 6 female table tennis players
A.C2/5C2/6 B.C2/5A2/6 C.C2/5A2/2C2/6A2/2 D.A2/5A2/6
In that case, the number before the "/" refers to the number above and the number below the "/" refers to the number below
It's better to analyze each one. Thank you very much.

The answer should be B
Choose two C2 / 5 from five male players, and then two from six female players. But note: at this time, the two female players have a relationship with which male player, so it is A2 / 5

Factorization of 2XY XX YY + 1

2xy-xx-yy+1
=1-(x-y)^2
=(1-x+y)(1+x-y)

There are 180 students in the fourth grade of a school, and the number of students in the fifth grade is one third of that in the fourth grade,
How many students?

180 times 1 / 3 times 4 / 5
=60 times 4 / 5
=48 (person)

Given that the square roots of a number are a + 3 and 2a-15, find the absolute value of the root sign (a-5) 2 + 3-a
Find the absolute value of the second power + 3-A of (a-5) under the root sign

The sum of the square roots is 0
a+3+2a-15=0
3a-12=0
a=4
√|(a-5)²+|3-a|
=√|(4-5)²+|3-4|
=|-1|+|-1|
=2