The sides of the parallelogram are 12 and 15 cm, the angle between them is 150 degrees, find the area

1. The tops of the parallelogram – A, B, C, D. AB = 12 centimeters. BC = 15 centimeters. ВН – height (drawn to the side of blood pressure). S is the area of the parallelogram. ∠В = 150 °.

2. ∠АВН = ∠В – ∠СВН = 150 ° – 90 ° = 60 °.

3. We calculate the length of the height of the ВН through one of the trigonometric functions ∠АВН (cosine):

BH / AB = cosine ∠ABH = cosine 60 ° = 1/2.

BH = 12 x 1/2 = 6 centimeters.

4. S = ВС х ВН = 15 х 6 = 90 centimeters².

Answer: S equals 90 centimeters².