# In the parallelogram ABCD, the angle A is 2 times less than the angle B. Determine all the angles of the parallelogram.

1. Let us denote the angle by the symbol ∠.

2. Since ∠А is twice less than В according to the problem statement, ∠В = 2 .А.

3. According to the properties of the parallelogram, the total value of the angles adjacent to one and its sides is equal to 180 °.

4. With this in mind, we compose the following expression:

∠А + ∠В = 180 °. Replace ∠B with 2∠A:

∠А + 2∠А = 180 °.

3∠A = 180 °.

∠А = 60 °.

∠B = 2 x ∠A = 2 x 60 ° = 120 °.

5. Opposite angles of a parallelogram are equal (according to its properties):

∠С = ∠А = 60 °.

∠D = ∠В = 120 °.

Answer: ∠С = ∠А = 60 °, ∠Д = ∠В = 120 °. 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.