Math questions, give a high score after answering! Math problems, solve! High scores.

1.The area of the western region referred to in China's large-scale development of the western region is about 6,850,000 square kilometers, which can be written as (685) 10,000 square kilometers, accounting for about the total area of the country.

2.The average daytime temperature on the surface of the Moon is minus 126°C, which is denoted as +126°C; The average nighttime temperature is minus 150°C, which is denoted as -150°C.

3.:2 ) 4 = 3 ( 6 ) = ( 50 ) % = ( ) fill in the decimal place).

4.The difference between the two numbers A and B, three-quarters of the number A and five-sixths of the number B are equal, and the sum of the two numbers of A and B is ( ).

5.The least common multiple of two numbers is 1200, and the greatest common factor is 20, and if one of these two numbers is known to be 80, then the other is (300).

6.In the right parentheses, fill in the heterodenominator fraction (3 4) + 1 6 ) = 11/12 with both denominators less than 12.

7.If quarters of y = three-quarters of x, then x and y are (inversely) proportional; If quarter y = thirds x, then x and y are (positive) proportional. (x,y are not 0).

8.The ratio of girls to boys is 4:5, with 20% fewer girls than boys and 25% more girls than girls

The homework is still good by yourself, if it is difficult to ask it, it can be understood, this kind of question is not very difficult, I believe you will do it yourself.

2 +102°c

4 x = 4 y = Answer.

6 1/6 3/4.

7 Positive.

1.When x=3, the algebraic value of ax 3+bx+8 is 12, and when x=-3, find the value of ax 3+bx-5.

27a+3b=4

a=-3,-27a-3b-5=-4-5=-9

How many times is this a few nomials? What is the highest sub-term? What is the coefficient for the highest subterm? What is the constant term?

This is a quadratic hepnomial, the highest order term is -3x 3y, the coefficient of the highest order term is -3, and the constant term is 1

y 2-1+x 3, how many times is this a few terms? What is the highest sub-term? What is the coefficient for the highest subterm? What is the constant term?

This is a quadratic quadrive, the highest minor term is -1 3x 2 y 2, the coefficient of the highest minor term is 1 3, and the constant term is -1.

4.If -2ax m is a monomial about x, y, and the coefficient is 4 and the order is 3, what is am+1?

If the coefficient is 4, then 2a=4, so a=-2, and the number is 3, so m=3, so am+1=(-2)*3+1=-5

5.If (k-5)x |k-2|y 3 is the 6th degree monomial about x and y, and the value of k is found.

Because this is a 6-fold form, it |k-2|3 6, so |k-2|3, so k = -1 or 5, and when k = 5 the coefficient is 0 and the mononomial is 0, it is not 6 times. So round off 5, so k=-1

6.If m is a constant and the algebraic formula mxy+2x-3y-1-4xy is a trinomial, then the value of 1 2m 2-m+2 is ?

mxy+2x-3y-1-4xy=(m-4)xy+2x-3y-1 is a trinomial, so m=4

7.Knowing that 1 2a 2x-1b 4 and -5a 3 b 3y-1 are the same terms, find the value of 2x-y.

From the definition of the same term, we can get the following: 2x-1=3, 3y-1=4, so x=2, y=5 3, so 2x-y=7 3

8.There is such a question: when a=, b=, the value of the polynomial 7a 3-6a b+3a 3+6a b-3a b-10a 3, a student said that the condition 'when a=, b=' is redundant, is his statement reasonable?

7a 3-6a b+3a 3+6a b-3a b-10a 3=, I don't know if this title was copied by mistake.

9.Knowing that the monomial 2mx ay and -5nx 2a-3 y are monomials about x,y, and are homogeneous terms, find the value of (4a-13) 2011. If so, find the value of (2m+5n-1) 2010.

From the definition of the same term, it can be obtained: a=2a-3, so a=3, so(4a-13) 2011 ( 1) 2011 -1.

2mx a y+5nx 2a-3 y 2mxy+5nxy=(2m+5n)xy=0, and xy is not equal to 0, so (2+5n)=0, so (2m+5n-1) 2010 ( 1) 2010 1

It's very simple.

1:27a+3b=4

a=-3,-27a-3b-5=-4-5=-92: cubic hexanomial; -y^3;-1;1

3: cubic quinnomial, x 3; 1,-1

4:m=3,a=-2,am+1=-5

5: The absolute value of k-2 is 3, k cannot be 5, k=-16: mxy and -4xy are combined into 0, m=4, 8-4+2=67: the question seems to be a bit problematic.

8: Simplify the original formula to -3a b, the title should be wrong, according to the meaning of the title, after simplification, it should not contain a, b, in order to say that he is redundant, otherwise, it is not redundant.

9: 2a-3=a, a=3, original = (-1) 2010 = 12m + 5n = 0, original = (-1) 2010 = 110: a = 1, b = -2, original = -10-8 9 + 9 2 + 2-4-5 = -15 and 7/18.

I think you made a mistake in question 10 and the number is strange.

Connect the OB OD

Proof of AOB COD

oa=oc=ob=od (because they are all the radius of a circle) a c so congruent.

So ab=cd

Extend the circle of CO to E, extend the circle of AO to F, connect DE, BF, because CE is the diameter, so CDE is 90°, the same is ABF=90°, and a C, CE=AF, the triangle CDE is congruent with ABF, AB=CD