Solve the following equation. Write out the process (1)4x－2＝3－x (2)－7x＋2＝2x－4

Solve the following equation. Write out the process (1)4x－2＝3－x (2)－7x＋2＝2x－4

(1)4x－2＝3－x
4x+x=3+2
5x=5
x=1
(2)－7x＋2＝2x－4
2+4=2x+7x
6=9x
2=3x
x=2/3

Use equation to solve a problem (the solution and setting should be written out, and the process can be omitted)
Uncle Wang, who has the courage to challenge the difficulties, contracted 25 mu of land and boldly improved eggplant and tomato in spring, with a total investment of 44000 yuan. Among them, 1700 yuan was invested in planting eggplant per mu, and the net profit per mu was 2400 yuan; 1800 yuan was invested in planting tomato per mu, and the net profit per mu was 2600 yuan, What is the total profit? (1 mu ≈ 0.067hm ^ 2)

If Uncle Wang planted x Mu eggplant, tomato would be 25-x
1700X+1800(25-X)=44000
We can calculate the number of Eggplant and tomato per mu
2400 * per mu eggplant + 2600 * per mu tomato is the amount he can make a profit

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、

About Y-X of x ^ 2-y ^ 2

Y-X of x ^ 2-y ^ 2
be equal to
(x + y) (X-Y) - (X-Y)
Share, gain
-（x+y）
be equal to
-x-y

Formula method for solving quadratic equation of one variable 25 (x-3) = 49 (2x + 3)
To solve the quadratic equation of one variable 25 (x-3) = 49 (2x + 3) by formula method, we only need how to extract the common factor instead of solving it,

25x-75=98x+147
Item transfer: 73x = - 222
The solution is: x = - 222 / 73

Given X & sup2; - 2xy-3y & sup2; = 0, then the value of 3x-2y / 3x + 2Y is
A.7/11
B.5
C. 7 / 11 or 5
D. None of the above is true

(x-3y) (x + y) = 0, x = 3Y or x = - y
When x = - y, (3x-2y) / (3x + 2Y) = - 5Y / - y = 5
When x = 3Y, (3x-2y) / (3x + 2Y) = 7Y / 11y = 7 / 11
CCC

The first solution is the first order equation of one variable, and the following are all solved by the first order equation of one variable
1) A person deposits $1500 in a bank for a fixed period of two years, assuming that the annual interest rate is 3% (excluding compound interest) and the interest income tax (tax rate is 20%) is deducted when the person withdraws at maturity. The actual interest earned by the person is -————
2) Xiaoliang deposits 8500 yuan in the bank as a one-year fixed deposit with an annual interest rate of 2.2%. When he withdraws money at maturity, he can get interest of () yuan. After deducting the interest tax (the tax rate is 20%), how much does it really get?
No one will

1.1500*3%*2*(1-20%)=72
2.8500*2.2%=187
187*(1-20%)=149.6

How to solve a quadratic equation with three unknowns
The general binary linear equation has two unknowns X and Y. how to solve the binary linear equation with three unknowns x, y and Z

This is a system of linear equations of three variables
You can cancel an unknown by substitution or addition and subtraction
Thus, it is reduced to a system of linear equations of two variables, and then solved
Finally, the values of the two unknowns are substituted into one equation and the third one is obtained

If the square-ax-1-a of the polynomial x about X is a complete square, what is a equal to

x^2-ax-1-a=x^2-ax+a^2/4-a^2/4-1-a=(x-a/2)^2-a^2/4-1-a
The solution is a = - 2

Let u = {0, 1, 2, 3}, a = {x ∈ u | x2 + MX = 0}, CUA = {1, 2}, then the value of real number m is ()
A. -3B. -2C. -1D. 0

∵ u = {0, 1, 2, 3}, a = {x ∈ u | x2 + MX = 0}, CUA = {1, 2}, ∵ 0, 3 ∈ a, M = - 3 can be obtained from 0 + 3 = - m, so a