In a right-angled triangle ABC with a hypotenuse AB, the height CD is drawn, the angle B is 60 °

In a right-angled triangle ABC with a hypotenuse AB, the height CD is drawn, the angle B is 60 °, the segment BD = 1 cm. Find the length of the hypotenuse AB.

Since CD is height, triangle CDB is right-angled.

Since angle D is right and angle B is 60 °, then angle BCD = 180 ° – 90 ° – 60 ° = 30 °.

In a right-angled triangle, the leg against an angle of 30 ° is equal to half the hypotenuse. Therefore, the hypotenuse BC = 2 * BD = 2 cm.

Consider a right-angled triangle ABC:

Since angle C is right and angle B is 60 °, then angle BAC = 180 ° – 90 ° – 60 ° = 30 °.

In a right-angled triangle, the leg against an angle of 30 ° is equal to half the hypotenuse. Therefore, the hypotenuse AB = 2 * BC = 2 * 2 cm = 4 cm.

Answer: 4 cm.



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.