Question

решите задачу.периметр первого прямоугольника 36 дм периметр второго составляет 80% от периметра первого , чему равна площадь каждого прямоугольника если их длина одинакова и равна 10 дм​

Answer 1

Ответ:

Пошаговое объяснение:

Найдём периметр второго прямоугольника

36:100*80 = 28,8 дм

Найдём сторону первого прямоугольника

( 36 - ( 10 + 10) ) : 2 = 8 дм

Найдём площадь первого прямоугольника

8 * 10 = 80дм в квадрате

Найдём ширину второго прямоугольника

( 28,8 - ( 10 + 10 ) ) :2 = 4,4 дм

Находим площадь второго прямоугольника

10 * 4,4 = 44дм в квадрате

Если десятичные дроби ещё не проходили переводи все в сантиметры. а потом опять все в дециметры .

Answer 2

#### Problem Analysis We are given two rectangles with the same length, and we need to find the area of each rectangle. The perimeter of the first rectangle is 36 dm, and the perimeter of the second rectangle is 80% of the perimeter of the first rectangle. #### Solution Let's solve the problem step by step: 1. Find the length of each side of the first rectangle: - The perimeter of a rectangle is given by the formula: perimeter = 2 * (length + width). - We are given that the perimeter of the first rectangle is 36 dm. - Since the length and width are equal in this case, let's assume the length of the first rectangle is 'x' dm. - Using the formula, we can write the equation: 36 = 2 * (x + x). - Simplifying the equation, we get: 36 = 4x. - Dividing both sides of the equation by 4, we find: x = 9 dm. 2. Find the perimeter of the second rectangle: - We are given that the perimeter of the second rectangle is 80% of the perimeter of the first rectangle. - The perimeter of the second rectangle is 80% of 36 dm. - Calculating 80% of 36, we get: 0.8 * 36 = 28.8 dm. 3. Find the length of each side of the second rectangle: - Since the length and width are equal in both rectangles, the length of the second rectangle will also be 'x' dm. 4. Find the area of each rectangle: - The area of a rectangle is given by the formula: area = length * width. - For the first rectangle, the length is 9 dm and the width is also 9 dm. - Calculating the area of the first rectangle, we get: area = 9 * 9 = 81 dm^2. - For the second rectangle, the length is also 9 dm and the width is also 9 dm. - Calculating the area of the second rectangle, we get: area = 9 * 9 = 81 dm^2. #### Answer The area of each rectangle is **81 square decimeters**. #### Explanation We found the length of each side of the first rectangle to be 9 dm using the given perimeter. Then, we found the perimeter of the second rectangle to be 28.8 dm, which is 80% of the perimeter of the first rectangle. Since the length and width are equal in both rectangles, the length of the second rectangle is also 9 dm. Finally, we calculated the area of each rectangle to be 81 square decimeters by multiplying the length and width.