Ask to write math problems, write the process, mark the question number, and thank you

22.Solution: y= 2x-3+ 3-2x+4 2x-3, 3-2x is meaningful.

2x-3≥0

3-2x≥0

x=3/2y=0+0+4=4

23.(1) Solution: Substitute x=2 and y=-3.

3=2k-4

The analytic formula of the function k=1 2 is y=x 2-42) solution: (translate the image of this number upwards by six units, i.e., b+6) The analytic formula of the translated function is y=x 2+2

Intersecting the x-axis is y=0).

Substitute y=0 into y=x 2+2

0=x/2+2

The coordinates of the point x=-4 are (-4,0).

23 questions, -3=2k-4

2k=1k=1/2

1)y=1/2x-4

2) Translate 6 units upward: y=1 2x-4+6y=1 2x+2 intersection with x-axis 0=1 2x+2x=-4y=1 2x+2 intersection with x-axis (-4,0)22 2x-3=0

x=3/2y=4

xy=4×3/2=6

1. Bring x=2 and y=-3 into the formula, -3=k*2-4, get k=, and the formula is y=

Translate 6 units upwards, that is, y-6=, and the formula obtained is y=2, and there are 2x-3 and 3-2x in the formula, which means that 2x-3=0, x=y=4, xy=6

The questions are very simple, but I don't know what level you are, so I'll use the easier method.

Question 1: If the lawn area is 84 square meters after 10 days, then it will be 42 square meters after 9 days, 21 square meters after 8 days, square meters after 7 days, and square meters on the seventh day.

If the equation assumes that the original lawn area is x square meters, we ask for the result x (7-1).

The known condition is x 10 = 84

then there is x 10 x (7-1)=2 3

x^(7-1)=x^10/2^4=84/16=

Question 2: I guess the question is the first day when 20 bacteria multiply to 5,000.

Let it be x days, and find the minimum value of x in inequality 20*2 (x-1)>=5000.

Solving the inequality gives 2 (x-1)>=250, and the minimum value of x is 9, i.e., 5000 can be reproduced on day 9.

In question 3, out of the 35 people who set up the language to apply for mathematics, x people must have taken the English test at the same time.

Among the 31 people who set up English to apply for English, Y must have taken the mathematics exam at the same time, and the remaining 31-y people must have taken the Chinese exam at the same time.

Column equations do.

x+y=34

35-x=31-y

Solution x 19, y 15

Since 35-x = 31-y = 16

Therefore, the number of applicants for both Chinese and English examinations is 16.

Question 4, the project can be completed by team A alone in x days, and team B can be completed in y days alone.

then there is 5 x+3 y 1

9/y+3/x＝1

Solution x 6, y 18

The number of days that team A does 1 day and team B can write an expression.

1-1 6)*18 15 i.e. Team B will take 15 days to complete.

2 9*2>5000 Day 9.

3.The conditions of the question are insufficient.

4.Let A be completed in x days and B in y days, 5 x+3 y=1 9 y+3 x=1 x=6 y=18

1:84 2=42 42 2=21 21 2= Answer: The area of the lawn on the seventh day is.

2: I always feel that there is a problem with the question, you have said "20 days to reproduce to 5000", but you ask "is the first day", a little incomprehensible.

3: 34 + 35 + 31 = 100 (person) 100 2 = 50 (person) 35 + 31 = 66 (person) 66-50 = 16 (person) Answer: There are 16 people who report both Chinese and English.

4: I'm sorry, forgive me for being an elementary school student, not for a while

2 9*2>5000 Day 9.

3.The question is wrong!

4.Let A be completed in x days and B in y days, 5 x+3 y=1 9 y+3 x=1 x=6 y=18

Solution: 9. Original formula = (a-b) (2n)(a-b) [2(n-1)](a-b) (2n+2n-2).

a-b)^(4n-2)

10. Original formula = -7(ab) 18+5a 18b 18-7(ab) 18+5(ab) 18

2(ab)^18

11. Original formula = 4a 6a 3+9a 2a 7-64a 94a 9+9a 9-64a 9

51a 912, original = x (4+3+5)+x 12+4x 12x 12+5x 12

6x 1213, original = x 8-2x (2+6)+x 82x 8-2x 8

14. Original formula = (-1) (-1) (-1) (a 9) * (a 3) * (a 3).

a^18

How can I send it to you on paper?

Question 1. There are 16 + 15 + 21 = 52 (people) who only participate in one subject, then the students who participate in at least two groups have a total of 110-52 = 58 (people), and (52-16) + (61-15) + (63-21) = 36 + 46 + 42 = 124 (people), then there are 124-58 * 2 = 8 (people) who participated in three groups at the same time (58 should be multiplied by 2 because these 58 people participated in at least two groups, the extra number of people, That is, the number of people who also participated in the third group, that is, the number of people who participated in three groups at the same time).

Question 2. After the large cube with a side length of 10 cm is disassembled, only the small cubes on the side of the large cube are painted with more than one face, that is, the number of small cubes in this part is found. There are a total of 36 + 36 = 72 small cubes in front and behind this large cube, and there are 16 + 16 = 32 on the remaining borders on the left and right, so there are a total of 72 + 32 = 104 (this question requires some spatial imagination...).

Question 3. The boy's 10 11 is twice as many as the remaining girls, then the remaining girls are 5 11 as the boys, that is, the remaining 156-12 = 144 after removing 12 girls is the boy's (1 + 5 11), that is, 16 11 times, then the boy has 144 (16 11) = 99.

Question 1: 16 + 15 + 21 = 31 + 21 = 52 for those who participate in a group, 110-52 = 58 for those who participate in a group

There were 36 participants in the language group.

There were 46 participants in the English group.

There were 43 participants in the mathematics group.

There are x people in three groups.

58-x=(36+46+43-3x)/2

116-2x=125-3x

x = 9 with 9 people.

Question II: 64

Question 3: Male x x 12 + 10 x 22 = 156 x = 99 .

1 set x to participate in 2 subjects, y to participate in 3 then there is 2x+3y=121, x+y=58 and then calculated.

2 is on the edge and on the corner, 8 times 12 + 8 = ...

3 still sets x,y

You should be a primary school student.,I don't know if I've learned a binary equation.,If you haven't learned it, you shouldn't have seen this answer.。。。

Solution 1: Let only those who participate in all three subjects be A, B for Chinese and English, C for Chinese and Mathematics, and D for English and Mathematics.

21+a+d+c=63 Solution 3: Let the boy x and the girl y.

16+b+c+a=52 (1-1/11)*x=(y-12)*215+a+b+d=61 x+y=156

a+b+d+c=110-16-15-21 Quaternary equation you can solve, so you can find x y.

Solution 2: This is actually a permutation problem.

Let's start with the big cube, which is made up of four vertical edges and eight edges that intersect them, so at least two sides are actually dyed on the edges: 10*4+8*8= give me some hard work, okay?

There were 36 participants in the language group.

There were 46 participants in the English group.

There were 43 participants in the mathematics group.

There are x people in three groups.

58-x=(36+46+43-3x)/2

116-2x=125-3x

x = 9 with 9 people.

Question II: 64

Question 3: Male x x 12 + 10 x 22 = 156 x = 99 .

22. According to the title: 2x-3>=0 x>=3 23-2x>=0 x<=3 2 So x=3 2 is substituted into the original formula: y=4

Therefore, xy=3 2*4=6

23. (1) Bring x=2, y=-3 into the primary function:

2k-4=-3

k=1 2, so the analytic formula y=1 2 x-4

2) Shift 6 upwards i.e

y=1/2 x-4+6=1/2 x+2

Let y=0, x=-4

So the intersection point with the x-axis is (-4,0).

21. Original formula = a 4b c 1 2ab c -(abc) 5=1 2a 5b 5c 5-a 5b 5c 5=-1 2a 5b 5c 5

22. Original formula = -x 6y 12 + 4x 6y 12 = 3x 6y 12

23. (1) Original formula =-(3 1 3) 2002 1 3=-1 3

2) Original = (1 2) 8 (-2 9) = -(1 2 2) 8 2 = -2

3) Original formula = 2 2003 (1 2) 2004 = (2 1 2) 2003 1 2 = 1 2

4) Original = (

5) Original formula = (1 2 11 3 2 3 11) 1999 (2 3 11) = 1 1999 6 11 = 6 11

21.Original formula = 1 2*(a 5b 5c 5)-a 5b 5c 5=-1 2*a 5b 5c 5

22.Original = -x 6y 12 + 4x 6y 12 = 3x 6y 1223(1) Original formula = (-3) 2002 (-3) 2003 = (-3) -1=-1 3

2) Original = 2 8 ( 2 9 = 2

3) Original = 2 2003 ( 2) 2004 = 2 1 = 1 2 (4) Original = [

5) Original = 11 6*6 11 1999 6 11=1 1999 6 11=6 11