1 1 ？？？Urgent! Junior high school math is so hard!

Two, because one plus one is inherently equal to two.

You're so funny, but it's still you 2

It's so hard, I really can't do it, is it 2?

(1) When P is in motion on AB, y=1 2 x 1=x 2 (0 x 1).

When P is in motion on BC, y=s square ABCD-S ABCD-S PCE-S ade

1-(x-1)/2-(2-x）/4-1/4

3-x）/4(1≤x≤2)

When P is in motion on CE, EP=CE-CP=1 2-(X-2)=,Y=1 2 (

Because the moving point p moves along a b c e (p point does not coincide with points a and e), it is not on ed.

This question should be discussed on a case-by-case basis, so the functional relationship between y and x is a piecewise function, i.e. what is written above.

2) x 2 = 1 3, the solution is x=2 3, in the range of 0 x 1, which is in line with the topic.

3-x) 4=1 3, the solution is x=5 3, in the range of 1 x 2, which is in line with the topic. , the solution is x=11 6, which is not in the range of 2 x, which is not in line with the topic, and is discarded.

So the value of x is 2 3 or 5 3

When encountering this kind of problem, you must first draw a sketch, and discussing the situation is the key to this question.

y=x/2,x≤1;y=(3-x)/4,1≤x≤2;y=(x-2)/2,2＜x＜;y=(,;You just need to divide it into four paragraphs: ab, bc, ce, ed, 2) y=1 3, when 2 is satisfied, then x=5 3

(1) Set c as Z, then x+y+z=10, 12x+10y+8z=100, and get 2x+y=10

2) (3) These two questions are relatively simple, just bring in the data one by one according to the equation provided in (1) (where x is greater than or equal to 2, y is greater than or equal to 2, and z is greater than or equal to 2).

Profit 36x 40y 16z

The interest rate of the annual potato banquet is 4% of the savings saved for x yuan, and 3% of the savings are 1000-x yuan.

4%*x+3%(1000-x)=

The two types of depositors carefully deposited 400 yuan and 600 yuan of this silver respectively.

1 degree is equal to 60 minutes.

1 minute and 60 seconds.

degree——。 Points——'

seconds'That should be clearer, huh.

1 180 degrees.

3 2520 degrees.

4 Let the number of each inner angle be x degrees, then the outer angle adjacent to it is x 5 degrees x 5 + x = 180

The solution is x=150 degrees.

Its outer angle is 30 degrees.

So, the polygon has 12 sides.

Answer: Each of its inner angles is 150 degrees; The polygon has 12 sides.

5 360 (3+1+2+3)=40 degrees 40*3=120 degrees.

1, 9 5/8 10

2 (1) is meaningful, the value inside the root number is greater than zero (2) is meaningless, the value inside the root number is less than zero.

3) Meaningful.

4) Be meaningful.

3. (1) 7 (or -7) (2) two-fifths (or minus two-fifths).

3) 1 in 1,000 (or minus 1 in 1,000) (4) or.

1.(1)9 (2)5/8 (3) (4)10

2.(2) The formula is meaningless, and the rest is meaningful.

3。(1) 7 or -7 (2) 2 5 or -2 5 (3) or (4) or.

9 5/8

Yes, the root number is positive none, the root number is negative, and the root number is positive.

Plus or minus 7 plus or minus 2 5 plus or minus 1 1000