Math Problems Check with Math Problems Check .

First, the question is incomplete.

2. A's work efficiency is 1 8, and B's work efficiency is (1 8) (4 3) = 3 32 Two people cooperate: 1 8 + 3 32 = 7 32

3. 100y+x

4. 32 (2+3)=32 5=

Fifth, set up x computer desks, then 15-x desks.

120*x+200*(15-x)=2200x=10，15-x=15-10=5

So I bought 10 computer desks and 5 desks. Sixth, two kinds.

7. I don't understand.

8. Let the unit digit of the original number be x, then the ten digit is 5-x

The original number is expressed as: 10*(5-x)+x=50-9x, and the new number is expressed as: 100*(5-x)+x=500-99x, and the sum of the two numbers is 334: 50-9x+500-99x=334 is solved to x=2, then the ten digits are 5-2=3

So this two-digit number is 32

Is there a problem with the first question?

The answer to the second question is c [Let the time be x, the equation is: (1 8 + 1 8*3 4) x = 7 8].

The answer to the third question is 100y+x

The answer to question 4 is 32 (3+2)=

The answer to the fifth question is a system of equations: (let the computer desk be x and the desk be y) x+y=15 and 120x+200y=2200

If you are satisfied, please click Accept as a satisfactory answer.

The square of 19-1 under the root number is wrong, and it should be 19+1-double the root number under 19, and the final answer is 17

The squared formula for the difference between two numbers:

a-b)^2=(a-b)(a-b)=a*a+b*b-2ab

The squared difference formula is applied incorrectly.

19 plus one minus two, root number 19 plus two, root number nineteen minus two minus one, waiting for you 17

<>9. Correction: A original: 22 (1-1 5) = yuan) B also has omissions: (yuan).

Answer: B also returned 30 yuan to Mazhou. Transport.

11.This question is correct.

12.Equal to , vector baVector coVector de.

Parallel there, vector coVector cfVector baVector de. Vector foVector ocVector fcVector abVectored.