Junior 1 math problems... Ask for answers... Write completely

Question 1: There are two cases: remove the absolute value 2004-2004x=20042004x=0

x=0, and the second case is 2004-2004x=-20042004x=-4008

x=2 Question 2 Because the number of hearts and clubs is the same, the chances are the same.

The number of spades is greater than that of the king and the king, so the chances of drawing the spades will be greater.

1.Just discuss it by category.

When 2004-2004x 0, 2004-2004x=2004x=0, when 2004-2004x 0, 2004x-2004=2004x=22I guess you haven't talked about the probability yet.

Because the number of hearts and plum blossoms is the same.

So the odds of drawing hearts are just as good as clubs.

The odds of drawing a spade are p1 = 13 54

The probability of drawing big and small kings is p2 = 2 54 = 1 27, so the probability of drawing spades is greater.

1) 2004-2004x=2004 or -2004. If it is equal to 2004 then x=0, if it is equal to -2004 then x=2 so x=0 or 2

2) Hearts and clubs are 13 cards so the odds are the same, and spades are 13 cards and 4 kings are kings, so the odds of spades are big.

Question 1|2004-2004x |=2004x 1 at 2004x-2004=2004

2004x=4008

x=2x<1 2004-2004x=20042004x=0

x=0 Question 2 1As big as 2Spades are large.

1.Known: |2004-2004x|= 2004, then 2004-2004x=2004 or 2004-2004x=-2004

Find: x=0 or x=-2

2.The chance of drawing hearts is as great as the plum blossoms! Do you have a better chance of drawing spades than big and small kings?

Suppose the daughter is now x years old, then the father is now 91-x years old. The age difference is 91-2x.

The father is 2x years old in the year, and the daughter is 2x-(91-2x)=4x-91 years old.

There is 3(4x-91)= 91-x

x = 28 daughter 28 years old, dad 63 years old.

Suppose the father and daughter are now n and m in age, respectively

2m-1/3 *n=n-m

3m=4/3 n

m=4/9 n

n+m=91

n+4/9 n=91

n=63 (years).

m = 91-63 = 28 (years).

Suppose the daughter is now x years old, then the father is now 91-x years old.

The father was 2x years old and the daughter was 91-2x years old.

There are 3(91-2x) = 91-x

Can I use a binary equation in the first year of junior high school?

If you can:

Suppose the father is now x years old and the daughter is y years old, x+y=91, 2y-x=x 3-y, and the solution is x=63, y=28.

Suppose the daughter is now x years old, then the father is now 91-x years old. When the father's age is twice the daughter's current age, and the father is 2x years old, then 2x-(91-x)=3x-91 years have passed. At this time, the daughter's age is x+3x-91=4x-91 years old.

Daddy is 1 to 3 years old (91-x) 3 years old, ie.

4x-91=(91-x) 3 solves x=28, then my father is now 63 years old.

Suppose the father is now x years old and the daughter is y years old, x+y=91, 2y-x=x 3-y, and the solution is x=63, y=28.

Let the father be x years old and the daughter be 91-x years old (91-x)*2-x=1 3x-(91-x) x=63

Suppose the father's current age is x years old and the daughter's current age is (91-x) years old. 2*(91-x)-x = one-third multiplied by x-(91-x).

1) Original formula = 8y-[x 2y-(3xy 2+2xy 2)]-5xy 2=8y-(x 2y-5xy 2)-5xy 2=8y-x 2y

Substituting x y into the original formula = 8 3-3 4 = 23 122) From the meaning of the title, it can be seen that without xy, then 3k+1 3=0 is easy to get k=-1 9

3) The question should be (3a-2) +l2+b-3l=0, if it is, then 3a-2=0 2+b-3=0 get a=2 3 b=1

5(2a-b)-2(4a-2b+2)-(3b+1/2)=10a-5b-8a+4b-4-3b-1/2

2a-4b-9/2

1. Simplify, original formula = 8y--5xy2=8y--5xy2=8y-x2y+3y2-2+4xy2-5xy2=-x2y-xy2+3y2+8y-2

Then substitute to get: original formula = one and one twelfth.

2. Original formula: x2=(3k+1 3)xy-3y2-8When 3k+1 3=0, that is, k=-1 9, xy

3, the original title is (3a-2)2+l2+b-3l=0, with the property of non-negative numbers: 3a-2=0, 2+b-3=0, so a=2 3, b=1, and then substituted into the original formula = minus three and six minutes one.

Let the side lengths of e and f be x, then.

The side lengths of b, c, and d are respectively.

2x x-1-1, x+1, the upper and lower sides of the large square are equal in length, i.e. (2x-1)+(2x-2)=x+x+(x+1), that is, 4x-3=3x+1

The area of the rectangle x=4 is.

1.If the donkey carries x bags of goods, then the horse carries 2 (x-1)-1 bags, so the equation can be obtained from the title.

x+2(x-1)-1=12, solving the equation yields x=5 bags, so the donkey carries 5 bags of goods and the horse carries 7 bags of goods.

2.Analysis: Since the speed of A and B is different, it must be faster than the distance of a slow circle, so we can, let's say, A and B have to meet in x minutes, so we can list the equation:

290x-250x=400, you can solve: x=10 minutes, so A and B meet after 10 minutes.

3.Let's assume a total deposit of x yuan, we first analyze that all the deposits in this donation activity plus the interest generated by these deposits have donated a total of 300 students, and each student needs 300 yuan per year, so we can get the equation:

x*(1+, solving this equation can obtain x=yuan, and the interest is x*yuan, (1) the interest obtained from this donation is yuan;

2) So total deposit yuan.

1 Solution: Set up donkey pack x bag, horse pack y bag.

This results in 2(x-1)=y+1

x+y=12

The solution is x=5 y=7

Answer: 5 bags for donkeys and 7 bags for horses.

2 400 (250 + 290) = min)3 dizzy ......

I don't understand why this number is ......

Again, I don't understand why interest is yuan.

3=4, after giving a bag, there are 4 left, indicating that there were 5 before, which are 7 and 5 respectively

3. I'm thinking too much and can't figure out the meaning of the question.

Let's say it's a dry cavity found after x minutes.

30 kmh = 30 1000 m 60 minutes = 500 m min.

2 km h = 2 1000 m 60 min = 100 3 m min.

100 3 5 + (500-100 3) x = (500 + 100 3) defeat (5-x).

The solution is x=5 2

A: It was found 5 2 minutes later.

Solution: Let's find out after x minutes. Repentance.

The speed against the water is (30-2) km/h.

The length of the water is (30+2) kilometers.

2（x+5）+28x=32*5

2x+10+28x=160

30x=150

x=5A: It was found after 5 minutes.

Solution, set the purchase price to x yuan.

List the system of equations by the title:

x=2700 A: The purchase price is 2700 yuan.

18 questions:

According to the question, RT ABC and RT AED are isosceles right triangles, AED= EAC=45°, then AOE=90° yields AC ED19:

1. Multiple choice questions.

8: Select d for an area of 9

2. Fill in the blanks.

9: Equilateral triangle.

10：13-3x2=7cm

11：360°-60°x2-90°=150°12：(180°-20°x2-30°x2)÷2=40°13：12x2x2-12=36

3. Answer questions.

1. Multiple choice questions:

1、d2、b

3、a4、a

5、c6、c7、d

You asked for a whole paper!!