Answer:
A right angle has a value of 90 degrees (90∘). A right triangle is a triangle in which one angle is a right angle. The relation between the sides and angles of a right triangle is the basis for trigonometry.
The side opposite the right angle is called the hypotenuse (side c in the figure). The sides adjacent to the right angle are called legs (sides a and b). Side a may be identified as the side adjacent to angle B and opposed to (or opposite) angle A. Side b is the side adjacent to angle A and opposed to angle