Ask a few math problems, and the A in the first year of junior high school will help, be fast .

1. Suppose that Xiao Wang runs x meters at a speed of 6 meters per second, then x 6 + (3000-x) 4 = 10 * 60, and the solution is x = 1800

Answer: Xiao Wang ran 1,800 meters at a speed of 6 meters per second.

2. The appearance is changed because of forging, but the volume remains the same.

So the volume is cubic meters.

The length is multiplied by the width known, so height = volume of base area.

Both meters. 3. Set the rope x

x=2 bamboo pole is.

1.Let the time of 6m s run be x s

6x+4(600-x)=3000

The solution is x=300 s

So it ran 6m at 1800m s

m^3h=v/s=

3.Set the length of the bamboo pole x m

x-(x+ solution gives x= m

So the rope is 2m long and the bamboo pole is long.

1) A total of 600 seconds, set the speed of 6m seconds, and ran for x seconds.

6x+4*(600-x)=3000 x=300 seconds Find 1800 meters.

2) The volume is unchanged Set the height to x x * find x = 27 meters.

3) Let the length of the rope be x and the bamboo pole be y x-y= y-x 2= find the length of the rope 2 meters and the length of the bamboo pole in meters.

1. If x meters are run, then x 6 + (3000-x) 4 = 10 * 60 to get x = 1800

2. Set the height to x meters, then get x = 27

3. If the bamboo pole is x meters long, the rope is long (x + m, (x + x =.)

Question 1 Let x,x 6 + 3000-x) 4 = 10 * 60 x = 1800

Question 2 x=27

Question 3 Let the bamboo pole be x and the rope be (the rope is folded in half to be (.)

Column equation ( x=

1.a+b=0, cd=1, x2=1, x=1 or -1 original = 1-1-1=-1 or 1

So Xiao Ming wins.

3.）x=3,y=-2,xy=-6

0 (there is 0 in the formula, so don't consider it, it is 0) 6)x=20

y=-15 original=-4 3

1. a+b=0, cd=1, x 2=1, so the original formula = 1-x-1=-xx=1 or -1, so the original formula = 1 or -1

2. Xiao Mao: Xiao Ming: (-5)*(0

So Xiao Mao wins.

3, x=3, y=-2, so xy=-6

5. There are 0 in the integer greater than -3 and less than 4, so the product is 06, x=4*5=20, y=(-3)*5=-15, so the original formula =-(20) (15)=-4 3

Solution: 1).

After more than 10, one more is less, the lowest is 16, and 4 yuan is less, total: 4.

To buy at the lowest price, at least 40 + 10 = 50 pieces.

Buy 46, the difference is only 4 50, the lowest price = 16 + 4 * yuan.

For the first 10, profit 1 = 10 * (20-12) = 80 yuan.

6 the day after tomorrow, profit 2 = 36 * (

Total profit = 80 + yuan.

52: the first 10, profit 1 = 10 * (20-12) = 80 yuan.

Back 40: 40*(

The last 2: 2*(16-12)=8

Total profit: 80 + 718 + 8 = 806 yuan.

3) 1 2 + 1 2 to the 2nd power + 1 2 to the 3rd power + 1 2 to the 4th power +...1 2 to the 9th power.

4) Rule: Starting from 1, after the denominator is added to one, the denominator decreases and the numerator increases to be equal to the largest denominator.

Number of items per row: 27 50 is the 1+2+3+...75+27

1+75)*75 2+27=2877 items.

The first 200 = (1 + 19) * 19 2 + 10

Item 200 is 10 11

1, (1) 4 yuan = 10 bought first = 50, the minimum is 50, (2) 10 * 8 = 80, (46-10) * yuan (yuan yuan. (3) Count fifty first, and then count the two that are sold at 16 yuan, which is 80 + 42 * (16-12) = 244 yuan.

2, the first 1 3, the second 1 15....

That is, 1 2*(1-1 3)+1 2*(1 3-1 5)+

That is, 1 2*(1-1 3+1 3-1 5+1 5-1 7+...)1/2009）

That is, 1 2 * (1-1 2009) = 1004 2009 The third can only be done with high school knowledge.

At the beginning of the first question, the rest will not be gone.

20-16 = 4 4 40 10 = 400 (part).

A purchase of 46 made a profit, and 52 made a profit of 26 yuan.

1、a²+b²-4a+8b+20

a²-4a+4+b²+8b+16

a-2)^2 + b+4)^2

0 so a= 2 b= -4

So a+b = -2

2. A +b +c -ab-bc-ca multiply by 2 and divide by 2 ====3