Let the area of a rectangle be a, and its perimeter s be expressed as a function of side length X Why not s = 4x

Let the area of a rectangle be a, and its perimeter s be expressed as a function of side length X Why not s = 4x

Let the area of a rectangle be a, and its perimeter s be expressed as a function of side length X
S=2(x+A/x)
A / X is the length of the other side of the rectangle
Not s = 4x, because the adjacent sides of a rectangle are not necessarily equal. Only a square in a rectangle is equal
You can't replace the general with the special

Given that the perimeter of a rectangle is 6 and the length of one side is x, what is the functional relationship between its area y and X?

y=x^2-3x(0

Write out the following functional relations respectively, and point out the relationship between constant and variable, independent variable and function (1) the relationship between circle area s and diameter D
(2) The relationship between the total sales amount y yuan and the number of bottles sold x

1) S=πd²/4
Constant π / 4, variable D, s
2)y=1.2x
Constant 1.2, variable x, y

Write out the following function expressions, and point out the constant and variable, independent variable and function 1, triangle side length 4, height h, area s and height H
Write out the following function expressions, and point out the constants and variables, independent variables and functions
The relationship between area s and height h
2. There are 450 books lent to students today, and each student has 9 books. Then the relationship between the remaining number of books y and the number of students x is analyzed

1. S = 1 / 2 * 4 * H = 2h, where constant is 2, variable is h, s, independent variable is h, function is s
2. Y = 450-9x, where 450, - 9 are constants, variables are x, y, independent variables are x, and functions are y