Find the area of a rhombus whose sides are 7√2 cm and one of the corners is 135 °.

Let’s calculate the acute angle of the rhombus: 180 ° – 135 ° = 45 ° (the rhombus is a parallelogram, the sum of adjacent angles is 180 °).

The area of the parallelogram is S = a * b * sina (a and b are the sides of the parallelogram, a is the angle between them).

Hence S = 7√2 * 7√2 * sin45 ° = 49 * 2 * √2 / 2 = 49√2 (cm²).