The detailed process of addition, subtraction and elimination for the system of linear equations with two variables 3x + Y-5 = 0, 5x + 3y-15 = 0

The detailed process of addition, subtraction and elimination for the system of linear equations with two variables 3x + Y-5 = 0, 5x + 3y-15 = 0

3x+y-5=0 (1)
5x+3y-15=0 (2)
(1)×3-(2)
9x+3y-15-5x-3y+15=0
4x=0
x=0
y=5-3x=5

"Equation" is a very important mathematical model in real life. Please write an application problem of binary linear equations in combination with your actual life, and make the binary linear equations listed as x = 2yx + y = 60, and write the solving process

There are 60 trees in my family, of which poplar is twice as much as willow. How many trees are there for poplar and willow? According to the meaning of the question: x + y = 60 ① x = 2Y ② solution: x = 40y = 20 answer: my family has 40 poplar trees and 20 willows

Please use the above information to write an appropriate problem, list the binary linear equations, and write out the solution process
Read the following materials: a city taxi charge standard is: the starting price (3 kilometers) 6.00 yuan; 3 kilometers above 1.20 yuan per kilometer. Xiao Li takes a taxi 8 kilometers for the first time, costs 12.00 yuan, the second time takes a taxi 11 kilometers, costs 15.60 yuan. Thank you! Urgent! Urgent! Urgent!

A taxi in a city costs 1.20 yuan per kilometer after driving more than the starting price including kilometers. Xiao Li costs 12.00 yuan for the first 8 km taxi ride, and 15.60 yuan for the second 11 km taxi ride?
Set the starting price as X Yuan, including y km
1.2×（8-Y）=12-X
1.2×（11-Y）=15.6-X
The solution is: x = 6, y = 3
So the starting price is 6 yuan, including 3 kilometers

If an angle X is known to be an acute angle, then SiNx + cosx may be?
A.4/3
B.3/5
C.3/2
D.1/2
Please explain why

SiNx + cosx = radical 2Sin (x + 45)
0

Use a simple method to calculate the following questions. 20.36-7.98-5.02-4.36
117.8÷2.3－4.88÷023
9.56×4.18－7.34×4.18－0.26×4.18
And the next two

20.36－7.98－5.02－4.36 = 20.36－4.36 －(7.98+5.02)=16-13=3

When passing through the point P (- 1,1), make the intersection of the line and the square of the ellipse 4 / x + 2 / y = 1 at two points a and B. if the midpoint of the line AB is exactly the point P, find the intersection of the line where AB is located
Find the equation of AB line

The elliptic equation is X & # 178; + 2Y & # 178; = 4. Let the ends of strings be a (x1, Y1), B (X2, Y2) ‖ X1 + x2 = - 2, Y1 + y2 = 2A, and B are all on the ellipse ‖ X1 & # 178; + 2y1 & # 178; = 4 -------- ① x2 & # 178; + 2Y2 & # 178; = 1 -------- ② ① - ② (x1 & # 178; - x2 & # 178;) + 2 (Y1 & # 178; - Y2 & # 178;)

24 △ 3 = 8, so 24 is a multiple and 3 is a factor______ (judge right or wrong)

According to the meaning of factors and multiples, we can know that: 24 △ 3 = 8, so 3 and 8 are the factors of 24, and 24 is the multiples of 3 and 8. Factors and multiples are relative and cannot exist alone; so the answer is: ×

If the equation of X: x2-x + M = 0 has a solution on the closed interval of - 1,1, then the value range of real number m is

From x ^ 2-x + M = 0
m = - x^2+x,x∈[-1 ,1]
- x^2+x=-(x^2-x+1/4)+1/4=-(x-1/2)^2+1/4
The axis of symmetry is x = 1 / 2 ∈ [- 1, 1], and the opening is downward
Therefore, m takes the maximum value at 1 / 2, and in the interval [- 1, 1], 1 / 2 is farthest from - 1, so it takes the minimum value at - 1
The minimum value of x = - 1 is - 2 and the maximum value is 1 / 4
So the value range of real number m is [- 2,1 / 4]

A number that is not equal to 0 divided by 0.01 is ()
A. Expand 10 times B. expand 100 times C. shrink 10 times D. shrink 100 times

To divide a number not equal to 0 by 0.01 is to enlarge the number by 100 times

Using equation method to solve equations 3x-2y = - 10 ① 3x + 2Y = - 2 ②
Solving equations by equation method
(1) 3x-2y=-10① 3x+2y=-2②
(2) 6y-7x=40① 5x-2y=-8②
(3) 3/x+y/4=4/3① 4（x+2=3(y-4)②
(4) x+y/2+x-y/2=7① 4(x+y)-5(x-y)=2②

1. 6x = - 12 x = - 2 is obtained by adding 2 to 1. Y = 2 is obtained by substituting x = - 2 into 1
The rest of the same reason, these problems are not difficult, to do well oh