Решение #
A right angle is an angle which is exactly 90.
An acute angle is an angle which is less than 90.
An obtuse angle is an angle which is more than 90 but less than 180°.
An isosceles triangle is a triangle with two sides of equal length.
An equilateral triangle is a triangle in which all the sides are of equal length.
A right triangle is a triangle in which one of the angles is exactly 90.
Hypotenuse is the longest side of a right triangle which is opposite the right angle.