Question

Периметр прямоугольника равен 76см. Найди его площадь если ширина меньше длины на 4 см.

Answer 1

Р=2·а+2·в

Пусть ширина будет х, тогда длина будет х+4, составим уравнение:

2·х+2·(х+4)=76

2х+2х+8=76

4х+8=76

4х=76-8

4х=68

х=68:4

х=17

Значит ширина х=17см, а длина х+4=17+4=21см.

Найдем площадь:

S=а·в

S=17·21=357см².

Answer 2

Problem Statement

We are given that the perimeter of a rectangle is 76 cm, and the width is 4 cm less than the length. We need to find the area of the rectangle.

Solution

Let's denote the length of the rectangle as L and the width as W.

From the given information, we know that the width is 4 cm less than the length. Therefore, we can write the equation:

W = L - 4 The perimeter of a rectangle is given by the formula:

Perimeter = 2 * (Length + Width) Substituting the values into the formula, we have:

76 = 2 * (L + (L - 4))

Simplifying the equation, we get:

76 = 2 * (2L - 4)

Dividing both sides of the equation by 2, we have:

38 = 2L - 4

Adding 4 to both sides of the equation, we get:

42 = 2L

Dividing both sides of the equation by 2, we find:

L = 21

Substituting the value of L back into the equation W = L - 4, we have:

W = 21 - 4 = 17

Therefore, the length of the rectangle is 21 cm and the width is 17 cm.

To find the area of the rectangle, we use the formula:

Area = Length * Width

Substituting the values, we have:

Area = 21 * 17 = 357 cm^2

So, the area of the rectangle is 357 cm^2.

Answer

The area of the rectangle is 357 cm^2.