It is known that the line L is parallel to the line L: y = 2x-3, and the intercept of the line on the Y axis is 4

It is known that the line L is parallel to the line L: y = 2x-3, and the intercept of the line on the Y axis is 4

The line L is parallel to the line L: y = 2x-3
So k = 2
The intercept of the line on the Y axis is 4
So the straight line passes (0,4)
So the linear equation is y = 2x + 4

Simple calculation method of 0.39/0.4/2.5 * 1.61

0.39÷0.4÷2.5*1.61
=0.39÷（0.4×2.5）*1.61
=0.39÷1*1.61
=0.39*1.61
=0.6279
This is the first answer

1. There are 162 students in class A, class B and class C of a certain school. The number of students in class B is 12 less than six fifths of that in class A. the number of students in class C is 17 more than two thirds of that in class B. how many students are there in class A, class B and class C
2. For a project, it takes 16 hours for team a to complete it alone and 24 hours for team B to complete it alone. Now team B will do it for 5 hours, and then two couples will cooperate. How many more hours can we finish five eighths of the whole project?
3. The price of a certain commodity is 226 yuan. If you sell it at a 70% discount, you can still get 13% profit. How much is the current purchase price?
4. Both Party A and Party B start from place a to place B, and Party A walks while Party B rides a bicycle. If Party A starts 6km before Party B starts, Party B will arrive at place B at the same time as Party A after two-thirds of an hour; if Party A starts for one and half an hour, Party B can catch up with Party A in one hour to find the distance between a and B
5. Xiaozhang's waterway from a to B is 40 km shorter than the highway. At 11 a.m., a ship sails from a to B, and at 2 p.m., a car sails from a to B. they arrive at B at the same time. It is known that the speed of the ship is 24 km per hour, and the speed of the car is 40 km per hour

1. There are x people in class A, y people in class B and Z people in class C
｛x+y+z=162
｛5/6-12=y
｛2/3y+17=z
The solution is x = 55, y = 54, z = 53
A: there are 55 in class A, 54 in class B and 53 in class C
2. Efficiency of team a: 1 / 16 = 1 / 16, efficiency of team B: 1 / 24 = 1 / 24
1/24*5=5/24
(5 / 8-5 / 24) / (1 / 16 + 1 / 24) = 4 (hours)
A: another 4 hours can complete 5 / 8 of the whole project
3. 226 * 70% = 158.2 yuan
Suppose the purchase price is x yuan
(158.2-x)÷x=13%
x=140
A: the purchase price is 140 yuan
I'm really tired of coding. I'm sorry. Please ask someone else^_^

If y is a linear function of X, the image passes through a point (- 3,2) and intersects a line y = 4x + 6 with a point on the x-axis, the analytic expression of the function is obtained
I know the answer is y = (- 4 / 3) X-2, but I don't know how to read it

Because it intersects with the straight line y = 4x + 6 and a point on the x-axis, that is, it intersects at (- 3 / 2,0)
Let y = K (x + 3 / 2)
Substitution point (- 3,2)
We get k = - 4 / 3
By substituting, we get a function of degree y = - 4 / 3 * (x + 3 / 2), that is, y = (- 4 / 3) X-2

It is known that the function f (x) = 2cos ω x (ω > 0), and the distance between two adjacent symmetry axes of the function y = f (x) image is π / 2
(1) Finding the value of F (π / 8)
(2) By extending the function y = f (x) to the right π / 6 and the abscissa by 4 times, the image of y = g (x) is obtained, and the monotone decreasing interval of G (x) is obtained

The distance between two adjacent symmetrical axes is π / 2
T=π/2*2=π
ω=2π/T=2
f(x)=2cos2x
(1)f(π/8)=2cosπ/4=√2
(2) g(x)=2cos(x/2-π/3)
2kπ≤x/2-π/3≤π+2kπ
Monotone decreasing interval of G (x)
2π/3+4kπ≤x≤8π/3+4kπ

Seek poems, couplets, riddles, sayings, proverbs and idioms about bridges~~
More is better~

1. The origin of the name of the bridge (1). Wuting bridge is located in the Slender West Lake of Yangzhou. The bridge foundation is made of 12 bluestone piers of different sizes. The body of the bridge is in the shape of arch roll, which is combined by three different roll holes, with a total of 15 holes. The holes are connected, and the corridors between the pavilions are connected. (2) the cross bridge is located in Jinci, Taiyuan City, Shanxi Province

First remove the brackets, and then merge the similar terms. X - (3x-2) + (2x-3); (the 2nd power of 3A + a-5) - (the 2nd power of 4-A + 7a)

x-（3x-2）+（2x-3）
=x-3x+2+2x-3
=-1
(power 2 of 3A + a-5) - (power 2 of 4-A + 7a)
=3a²+a-5-4+a-7a²
=-4a²+2a-9

If the solution set of inequality ax ^ 2 + BX + 2 > 0 is {x-0.5 ＜ x ＜ one third}, what is the value of a + B?

We know that A

All integer solutions satisfying inequality X-1 with absolute value less than 4 are

-4

It is known that y = f (x) is an even function defined on R, which is a decreasing function on [0 + &). Find the size relation of F (- 3 / 4) and f (a2-a + 1)
&Denotes positive infinity

a² - a + 1
= (a - 1/2)² + 3/4
≥ 3/4
Because f (x) is a decreasing function on [0, + ∞)
So f (A & # 178; - A + 1) ≤ f (3 / 4)
Because it's an even function
So f (- 3 / 4) = f (3 / 4)
So f (A & # 178; - A + 1) ≤ f (- 3 / 4)