The width of a rectangle is x meters, the length is three times of the width, then the length is () meters, the perimeter is () meters, and the area is () square meters

The width of a rectangle is x meters, the length is three times of the width, then the length is () meters, the perimeter is () meters, and the area is () square meters

The length is (3x) meters, the perimeter is (8x) meters, and the area is (3x & sup2;) square meters

A rectangular grassland has an area of 24 square meters and a perimeter of 22 meters
For length and width, it is better to use substitution or hypothesis
It's ok if you don't use it. Add another 20 points if you use it

S = AB, C = 2 (a + b); substituting s = 24, C = 22 to solve simple equations, a = 3, B = 8, or a = 8, B = 3;

There is a rectangular grassland with a circumference of 40 meters and a ratio of length to width of 3:2. How many square meters is the area of this grassland?

3+2=5
40÷2×2/5=8
20-8=12
12 △ 8 = 96 square meters
The grassland area is 96 square meters

Mr. Li put together a rectangle with eight pieces of colored square paper of the same size. The total area is 392 square centimeters. Can you find out the longest circumference of the rectangle?

The area of a small square color paper is 392 △ 8 = 49, and because 7 × 7 = 49, the side length of each small square is 7 cm, (1) one line arrangement: (7 × 8 + 7) × 2, = 63 × 2, = 126 (CM), (2) 2 × 4 arrangement: (7 × 4 + 7 × 2) × 2, = 42 × 2, = 84 (CM), answer: the longest circumference of the rectangle is 126 cm