If the hypotenuse and a leg of one right triangle are equal to the hypotenuse and leg of another right triangle, then the triangles are congruent.

All right triangles have two legs, which may or may not be congruent. The legs of a right triangle meet at a right angle. The other side of the triangle (that does not form any part of the right angle), is called the hypotenuse of the right triangle. This side of the right triangle will always be the longest of all three sides. The angles of a right triangle that are not the right angle must be acute angles.

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