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Fill in the blanks? (23 19:11:9) 9. Calculation: 1-2 + 3-4 + 5-6 +. + 2007-2008 + 2009=——
1-2+3-4+5-6+.+2007-2008+2009
=1-2+(3-4)+（5-6）+.+（2007-2008）+2009
=1005
How to solve the problem of filling in the blanks in the first year of junior high school
If the ratio of the degree of each inner angle of a Pentagon is 2:3:4:5:6, the complementary angle of the largest angle of the Pentagon is_____ .
If one angle of a quadrilateral is a right angle and the degree ratio of the other three angles is 2:3:4, then the degrees of the three inner angles are______ .
The answer and the process, thank you
If the ratio of the degree of each inner angle of a Pentagon is 2:3:4:5:6, the complementary angle of the largest angle of the Pentagon is___ 18__ .
The sum of the inner angles of an n-polygon is 180 * (n-2), which is a theorem
So the sum of inner angles of a Pentagon is 180 * (5-2) = 540
540/(2+3+4+5+6)=27
Therefore, the inner angle degree of pentagon from small to large is 54, 81108135162
So the corresponding external angles are 126, 99, 72, 45 and 18 (180 - de in turn)
So the complement of the largest angle is: 18
If one angle of a quadrilateral is a right angle and the degree ratio of the other three angles is 2:3:4, then the degrees of the three inner angles are______ .
The sum of the internal angles of a quadrilateral is 360
The sum of the other three angles is 360-90 = 270
270/(2+3+4)=30
The other three corners are:
2*30=60
3*30=90
4*30=120
There are six boys and five girls, two for each
There are 15 choices for boys and 10 choices for girls in C62 by C52. For boys and girls, if one of the 15 choices for boys is a, then there are 10 choices for girls and 15 choices for a, and the result is 15 times 10, 150
If x + y = - 1, xy = 5, then XX + YY=
Is XX for X & sup2; and YY for Y & sup2?
If so, there are:
（x+y)²=（-1）²
x²+y²+2xy=1
Given xy = 5, then
x²+y²=-9
It seems impossible!
There are 180 students in Grade 6, of which the number who can play table tennis accounts for one ninth of the total number. The number who can play badminton is the number who can play table tennis
There are 180 students in Grade 6, of which the number who can play table tennis accounts for one ninth of the total number. The number who can play badminton is six fifths of the number who can play table tennis. How many people can play badminton?
Those prawns on the Internet know it. Tell me about it to this math rookie,
Playing table tennis 180 × 1 / 9 = 20, playing badminton 20 × 6 / 5 = 24
Find the sum of all integers whose absolute value is greater than 1 but not greater than 5, the opposite number of - two fifths is, and the reciprocal is
Find the sum of all integers with absolute value greater than 1 but not greater than 5~
That is to say, 1
Number a is 18% smaller than number B, and number B is 20% larger than number C. which is the smallest of the three numbers?
If C is x, B is 1.2x, a is 0.82 * 1.2x = 0.984x, so a is the smallest
The letters e, e and B are written on the three cards respectively. The probability that the three cards will be randomly arranged in a line just as the English word bee is 0______ ．
From the meaning of the question, we can know that this question is a classical type. All the events included in the experiment can be listed. Three cards are randomly arranged in a line. There are three cases: bee, EBE and EEB. Only one meets the condition. The probability is 13. So the answer is: 13
A and B used to have several yuan each, and the amount of a's money was 5 / 8 of B's. If a spent 20 yuan and B spent 50 yuan, then the amount of money left by the two was the same
How much did a and B have?
Thank you very much
(50 -20) ÷ （1 -5/8）
= 30 ÷ 3/8
=80 yuan B
80 × 5 / 8 = 50 yuan a
The image and properties of inverse scale function
1. The inverse proportional function y = k is known
-If the coordinate of a point on the image (k is not equal to 0) is (- 1, root 2), then
X
The analytic expression of this inverse scale function is?
2. It is known that (2.1) on the image of inverse scale function y = K (k is not equal to 0), then the function image is one
-
X
Fixed point ()
What should a (- 2, - 1) B (- 2.1) C (- 1. - 2) d (2.1) choose?
I'm not good at math
Given that the point (2.1) is on the image of inverse scale function y = K (k is not equal to 0), then the function image is one
-
X
Fixed point ()
What should a (- 2, - 1) B (- 2.1) C (- 1. - 2) d (2.1) choose?
1. Y = - root 2x. (dizzy ~ can't play root) take x = - 1, y = root 2 into this formula, root 2 = K / - 1, so k = root 2 times negative one equals negative root 2. 2. Choose ACD (suspect that this problem is multiple choice, or you copy the problem wrong, it should be "must not go through something")
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