Question

Периметр прямоугольника равен 38 см. Его длина в 1, 5/7 раза больше ширины. найдите площадь прямоугольника

Answer 1

2а+2в=38   а=12/7в подставляем 2*12/7в+2в=38  24/7в+2в=38 решаем уравнение  24в+14в=266  в=7  а=12 площадь  7*12=84

Answer 2

Problem Analysis

We are given that the perimeter of a rectangle is 38 cm, and the length is 1 and 5/7 times the width. We need to find the area of the rectangle.

Solution

Let's assume the width of the rectangle is w cm.

According to the given information, the length of the rectangle is 1 and 5/7 times the width. So, the length can be expressed as (1 + 5/7)w.

The perimeter of a rectangle is given by the formula: P = 2(l + w), where P is the perimeter, l is the length, and w is the width.

Substituting the given values, we have: 38 = 2((1 + 5/7)w + w)

Simplifying the equation: 38 = 2(12/7w + 7/7w) 38 = 2(19/7w) 38 = 38/7w w = (38 * 7) / 38 w = 7 cm

Now that we have the width, we can find the length: Length = (1 + 5/7)w = (1 + 5/7) * 7 = 12 cm

The area of a rectangle is given by the formula: A = length * width.

Substituting the values, we have: A = 12 * 7 = 84 cm²

Therefore, the area of the rectangle is 84 cm².

Answer

The area of the rectangle is 84 cm².