Question

Периметр прямоугольника 40 см его ширина в 3 раза меньше длины чему равна площадь прямоугольника по действиям пожалуйста

Answer 1

x - ширина 

3x - длина

3x+x +x+3x= 40

8x = 40

x = 5 - ширина прямоугольника

3*x = 15 -длина

S = 15 * 5 = 75 см^2

Ответ: 75 см^2

Answer 2

Ширина меньше - значит длина больше
длина - 3 части
ширина-1 часть
1)3+1=4 части -длина + ширина
периметр это 2 длины +2 ширины
делим на 2 его
2)40:2=20 см это длина + ширина или 4 части
3)20:4=5 см -ширина или 1 часть
4)5*3=15 см длина или 3 части
площадь =длина * на ширину
5)площадь= 15*5=75 кв см

Answer 3

#### Problem Analysis We are given that the perimeter of a rectangle is 40 cm, and its width is 3 times smaller than its length. We need to find the area of the rectangle. #### Solution Let's assume the length of the rectangle is **L** cm. According to the problem, the width of the rectangle is 3 times smaller than its length, so the width is **L/3** cm. The perimeter of a rectangle is given by the formula: **2 * (length + width)**. We can use this formula to find the value of **L**. Given that the perimeter is 40 cm, we can write the equation as follows: **2 * (L + L/3) = 40** Simplifying the equation: **2L + 2L/3 = 40** Multiplying both sides of the equation by 3 to eliminate the fraction: **6L + 2L = 120** **8L = 120** Dividing both sides of the equation by 8: **L = 15** Now that we have the length of the rectangle, we can find its width by dividing the length by 3: **Width = L/3 = 15/3 = 5** The area of a rectangle is given by the formula: **length * width**. Substituting the values we found: **Area = 15 * 5 = 75 square cm** Therefore, the area of the rectangle is **75 square cm**. #### Answer The area of the rectangle is **75 square cm**. #### Explanation We found the length of the rectangle to be 15 cm and the width to be 5 cm. Using the formula for the area of a rectangle, we multiplied the length and width to find the area. The area of the rectangle is 75 square cm.