Mathematical problems known equation group {① ax + 5Y + C = 10 ② 4x by + 2D = 12} Xiao Wang copied a wrong in equation 1, Xiao Ming copied B wrong in equation 2. As a result, Xiao Wang's solution to the equation group is {x = 1, y = 1}, Xiao Ming's solution to the equation group is {x = - 1, y = - 1}, while the correct solution of the original equation group is {x = 2, y = 2}. You know a, B, C, try to find them (the process also needs)

Mathematical problems known equation group {① ax + 5Y + C = 10 ② 4x by + 2D = 12} Xiao Wang copied a wrong in equation 1, Xiao Ming copied B wrong in equation 2. As a result, Xiao Wang's solution to the equation group is {x = 1, y = 1}, Xiao Ming's solution to the equation group is {x = - 1, y = - 1}, while the correct solution of the original equation group is {x = 2, y = 2}. You know a, B, C, try to find them (the process also needs)

If x = 1, y = 1, 4x by + 2D = 12, we can get: 4-b + 2D = 122d-b = 8, x = 2, y = 2, 4x by + 2D = 12, we can get: 8-2b + 2D = 12d-b = 2, solve the equations: 2d-b = 8d-b = 2, we can get: D = 6, B = 4, x = - 1, y = - 1, ax + 5Y + C = 10, we can get: - a-5 + C = 10c-a = 15, x = 2, y = 2, ax + 5Y + C = 10, we can get: 2A + 10

Given the system of equations ax + 5Y = 15, 4x + by = - 2, a misinterprets A and gets x = - 3, y = - 1, B misinterprets B and gets x = 5, y = 4. If calculated correctly, what is the difference between X and y

According to the meaning of the title
-12-b=-2
5a+20=15
∴a=-1
b=-10
The equations can be reduced to
-x+5y=15
4x-10y=-2
It is necessary to solve this system of equations
x=14
y=29/5
∴x-y=14-29/5=41/5

The original price of a computer was 6000 yuan, which was first reduced by 1 / 12 and then increased by 1 / 10. Now how much is the price of this kind of computer?

6000*（1-1/12）*（1+1/10）=5500*1.1=6050

4-a2+4ab-4b2．

[algebra in grade one]
1) We know the system of equations about X, y
x+y=a+5
2x-y=3-2a
With positive integer solution, find the value of A
2) It is known that two positive integer solutions of a quadratic equation of two variables are
X = 2, y = 3 and x = 3, y = 1
① Try to find a positive coefficient equation satisfying this condition. Is there only one such equation?
② Find the rest of its positive integer solutions
>

The solution of the first problem is x = (8-A) / 3, y = (4a + 7) / 3
When a = 2, (x, y) is (2,5)
When a = 5, (x, y) is (1,9)
When a = - 1, (x, y) is (3,1)
The solution of the second question ax + by + C = 0 is a = 2B, C = - 7b, B = 1, and the equation is 2x + Y-7 = 0
(x, y) are (1,5), (2,3), (3,1)
(1,5) is the answer

Ma Zhe's discrimination: what has no use value must have no value, and what has value must have use value

What has value in use does not necessarily have value. What has value must have value in use. The attribute that can meet people's needs has value in use. Value in use is the natural attribute of commodity. The undifferentiated human labor condensed in commodity is the value of commodity. Value is the social attribute of commodity

A two digit number, the sum of ten digits and one digit number is 11, the new number is 63 larger than the original number after two digit transposition, find two numbers

Let the single digit be a and the ten digit be 11-A, so the original number is 10 (11-A) + A, and the changed number is 10A + 11-a
10A + 11-A = 10 (11-A) + A + 63, the solution is a = 9, so the original number is 29, and the changed number is 92

Question 13 on page 25 of mathematics book, Volume 2, junior high school, people's Education Press

13. Answer: because the two mirrors are parallel, so angle 2 = angle 3 (two straight lines are parallel, and the inner stagger angle is equal). So angle 1 = angle 2 = angle 3 = angle 4, so angle 5 = angle 6, and angle 5, and angle 6 are the inner stagger angle of two light rays (the light ray entering the periscope and the light ray leaving the periscope) cut by the light ray between the two plane mirrors, so the two light rays are parallel

Two diagonals AC and BD of parallelogram ABCD intersect at O, ab = radical 5, Ao = 2, OB = 1. Find the distance between parallel lines AB and CD
I don't have a picture

AB =, Ao = 2, OB = 1 form a right triangle
The height of side ab of right triangle AOB = 2 × 1 / √ 5 = 2 √ 5 / 5
The distance between parallel lines AB and CD is 2 times of the above data, namely 4 √ 5 / 5

What is the law of 4,3,6,9,8,27,10, (), ()

The odd digits are: 4, 6, 8, 10 () is the arithmetic sequence, and the arithmetic is 2, so it is 12;
Even digits are: 3 9 27 () is the power of 3, the first is 3 ^ 1, the second is 3 ^ 2, the third is 3 ^ 3, so the fourth is 3 ^ 4, the value is 81
Therefore, the two brackets should be: (81), (12)