The perimeter of the rectangle is 42cm, width is 6cm. Find the area.

Given:

rectangle ABCE,

AB = 6 centimeters,

R ABCE = 42 centimeters.

Find the length of the rectangle, that is, BC -?

Decision:

Consider the rectangle ABCE. Its opposite sides are equal to each other, then BC = AE, AB = CE = 6 centimeters.

R ABCE = AB + BC + CE + AE;

42 = 6 + BC + 6 + BC;

42 = 12 + BC + BC;

42 = 12 + 2 * BC;

42 – 12 = 2 * BC;

30 = 2 * ВС (in order to find an unknown factor, you need to divide the product by a known factor);

BC = 30: 2;

BC = 15 centimeters.

Answer: 15 centimeters.