In triangle ABC, angle C is 90 degrees, angle A = 30 degrees, AB = 40. Find the sun.

A triangle is three points that do not lie on one straight line, connected by segments. In this case, the points are called the vertices of the triangle, and the segments are called its sides.

A rectangular triangle is a triangle in which one corner is a straight line (equal to 90º). The side opposite the right angle is called the hypotenuse, and the other two are called legs.

In order to find the unknown BC leg, it is most convenient to use the sinus theorem. The sine of an acute angle of a right triangle is the ratio of the opposite leg to the hypotenuse:

sin A = BC / AB;

BC = AB · sin A;

sin 30º = 1/2;

BC = 40 1/2 = 40/2 = 20 cm.

Answer: the length of the BC leg is 20 cm.