There are a few math problems that everyone helps out in the first year of junior high school

That's all over, this should be good.

If there's anything you don't understand, just ask me.

or -24List the equation to get (a+b) a+b+c + m*m -cd0 c + 4 -1

5.Because |ab-2|with |b-1|is positive so ab-2=0 b-1=0

So b=1 a=2

1/ab = 1/a - 1/b

Then take it all apart in the whole about it.

Finally = 1 ab + 1 a + 2004 = 1 ab + 1 20066The analysis is as described above.

x=4 y=-2

So 2x-|y| = 2*4-2=6

Or -5, process: Let this number be x, 丨x丨=5, open it, and it will be the answer.

or -3, process: 丨x丨=3, open it out, and that's the answer.

Or -4, process: open 丨x-1丨=3, get: plus or minus (x-1) = 3, solve it, get 丨x丨=4, open it, that's the answer.

4.Equal to 1, process: because a and b are opposite to each other, so b = -a, because c and d are reciprocal to each other, so d = one part of c, substitute them into the formula, get:

a+(-a)] divided by the quadratic -cd, cd multiplied to get: -1, calculated, of: [a+(-a)] = 0, 0 divided by any number gives 0.

It's better to have a -1 left, so use 0-(-1)=0+1=1.

I'm sorry, but I'm sorry I can only do so much due to time constraints

、-1/2、-1/3、-1/4

4 non-fractions

4 non-negative numbers

4 integers (the answer is not unique).

2) Original = 2 + 4 + 6 + 8 + ....+4020

11042110 (buddy multiplication is hand-counted).

3) There is 1 term with a denominator of 1, 2 terms with a denominator of 2, and 3 terms with a denominator of 3 ......There are 14 terms with a denominator of 14 and 15 terms with a denominator of 15.

So 1 1 to 14 14 has 1+2+3+4+5+....+14=(1+14) 14 2=105 terms.

105 + 13 = 118 (terms), so 13 15 is the 118 terms of this series.

1 + 2 + 3 + 4 + 5 + 6 = 21 (terms).

That is, find the sum of all fractions with one denominator to six with a denominator.

Original = (1+2 2+3 3+4 4+5 5+6 6) +1 3+2 3+1 4+2 4+3 4+1 5+2 5+3 5+4 5+1 6+2 6+3 6+4 6+5 6)+1 2

6 + 4 + 1 2 = 10 and 1 2

4) (Pie) is a positive number, but it is not a positive rational number. Therefore, all irrational numbers greater than zero can be called positive numbers, but they cannot be called positive rational numbers. Positive numbers contain positive rational numbers.

Similarly- is a negative number, but not a negative rational number. So all irrational numbers less than zero can be called negative, but not negative rational numbers. Negative numbers contain negative rational numbers.

All finite decimals and infinite cyclic decimals can be converted into fractions, but infinite non-cyclic decimals cannot be converted into fractions, but all fractions can be converted into decimal format, and decimals contain fractions.

1、（1）2t－t＝15

2）（1－49％）a＝1020

3）80％b－10＝70

4）a＝45000÷30＋200

2. Solution: x-(x-1) 3=7-(x+3) 515x-5(x-1)=105-3(x+3)15x-5x+5=105-3x-9

10x+5=96-3x

13x=91

x=7, although I am also a ...... in the first year of junior high school

Helps you, right?

1.The number of middle school students in school is x, then 10% (32191-4217-x) + 23% x = 4217

There were 17,054 students in primary schools and 10,920 in secondary schools.

2.(1) 16,000 pieces (2) 300 people.

4 cubic meters in the month and 11 cubic meters in April.

1.The number of secondary school students in the school is x.

then 10%(32191-4217-x)+23%x=4217x=10920

There were 17,054 students in primary schools and 10,920 in secondary schools.

2.(1) 16,000 pieces.

2) 300 people.

3.The water used in March was 4 cubic meters, and in April it was 11 cubic meters.

The National Bureau of Land Planning and Fisheries and the Republic of Korea announced.

Collection of water and electricity bills and other links.