Given a rhombus ABCD with sides 12 cm. From the top A to the sides BC and CD two heights are drawn
June 10, 2021 | education
| Given a rhombus ABCD with sides 12 cm. From the top A to the sides BC and CD two heights are drawn, the angle between which is equal to 30 degrees. The perimeter of the rhombus = 48 cm. What is its area?
1. The heights AK and AH are drawn to the sides CD and BC, respectively. The angle between them is ∠HAK = 30 °. S is the area of the rhombus.
2. ∠DAK = 90 ° – ∠HAK = 90 ° – 30 ° = 60 °.
3. We calculate the length of the height of the AK in terms of one of the trigonometric functions ∠DAK (cosine):
AK / AD = cosine ∠DAK = cosine 60 ° = 1/2.
AK = 12 x 1/2 = 6 centimeters.
4. S = CD x AK = 12 x 6 = 72 centimeters².
Answer: S equals 72 centimeters².
One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.