A right angled triangle.
a right triangle
A rectangle has four sides whereas a right angle triangle has only three sides.
There are three sides.
A right angle triangle
right angle triangle
A right-angle triangle.
All triangles have three sides.
To calculate any of the three sides in a right triangle, if you know the other two sides; also, to verify that an angle is a right angle, if you know three sides of a triangle.
A triangle with a right angle and different lengths for sides is a right, scalene triangle.
Five side is always a pentagon, but there's no pentagon that always has exactly one right angle. A regular pentagon has no right angles. An irregular pentagon can have one, two, or three right angles, or none.
All triangles have three sides. If it doesn't have three sides, it's not a triangle.
It has 2 equal sides of right triangle.