Question

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

Answer 1

Пусть х - длина. Тогда ширина будет х - 4. Составим уравнение:
х + х + х - 4 + х - 4 = 76 
4х = 76+4+4
4х = 84
х = 84:4 
х = 21 (см) - длина прям-ка. 
21-4 = 17 (см) - ширина прям-ка. 
Sп = 21 * 17 = 357 см"2

Answer 2

Calculation of Rectangle's Area and Perimeter

To find the area and perimeter of a rectangle, we need to know the length and width of the rectangle. In this case, we are given that the perimeter of the rectangle is 76 cm, and the width is 4 cm less than the length.

Let's assume the length of the rectangle is L cm and the width is W cm.

Finding the Perimeter

The perimeter of a rectangle is given by the formula: P = 2(L + W).

Given that the perimeter is 76 cm, we can write the equation as: 76 = 2(L + W).

Since the width is 4 cm less than the length, we can express the width as: W = L - 4.

Substituting this value into the equation, we get: 76 = 2(L + (L - 4)).

Simplifying the equation, we have: 76 = 2(2L - 4).

Solving for L: 76 = 4L - 8, 4L = 84, L = 21.

Therefore, the length of the rectangle is 21 cm.

Substituting this value into the equation for the width, we have: W = 21 - 4, W = 17.

Therefore, the width of the rectangle is 17 cm.

Finding the Area

The area of a rectangle is given by the formula: A = L * W.

Substituting the values we found earlier, we have: A = 21 * 17, A = 357.

Therefore, the area of the rectangle is 357 square cm.

To summarize: - Length of the rectangle: 21 cm - Width of the rectangle: 17 cm - Perimeter of the rectangle: 76 cm - Area of the rectangle: 357 square cm.

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