The perimeter of the triangle is 36.8 cm and one of its sides is 13.8, calculate the area of the triangle.

We are given in the condition that the perimeter of the rectangle is 36.8 cm. It is also known that one side of the rectangle is 13.8 cm. To calculate the area of the rectangle, we must calculate the length of the second side of the rectangle.

Let’s denote by x cm the length of the second side of the rectangle.

To compose the equation, recall and apply the formula for finding the perimeter:

P = 2 (a + b);

2 (13.8 + x) = 36.8;

13.8 + x = 36.8: 2;

13.8 + x = 18.4;

x = 18.4 – 13.8;

x = 4.6 cm.

We find the area of the rectangle by the formula:

S = a * b = 4.6 * 13.8 = 63.48 cm2.