Given a right-angled triangle ABC with a right angle C, find angle A if angle B is greater than angle A by 40 degrees.

By the condition of the problem, the angle C is straight, which means it is equal to 90 degrees. By the property of triangles – the sum of all the angles of a triangle is 180 degrees. Let the angle A be equal to x, then the angle B is equal to (x + 40), we will compose the expression:

x + (x + 40) + 90 = 180.

Move the numerical values to the right, leaving the unknown on the left and solve:

x + x = 180 – 40 – 90

2x = 50

x = 50/2

x = 25

Angle A is 25 degrees, then angle B: 25 + 40 = 65 degrees.

You can easily check the correctness of the solution:

25 + 65 + 90 = 180 degrees.

Answer: Angle A is 25 degrees.



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.