The length of one leg of the triangle 
Further explanation:
The Pythagorean formula can be expressed as,

Here, H represents the hypotenuse, P represents the perpendicular and B represents the base.
Isosceles triangle has 2 sides equal to each other and the two base angles are equal to each other.
Given:
The length of the hypotenuse is 
The options are as follows,
(A). 
(B). 
(C). 
(D). 
Explanation:
The length of the hypotenuse is 
Consider the length of other leg of the triangle
.
Use the Pythagoras formula in triangle ABC.

Further solve the above equation.

Hence, the length of one leg of the triangle 
Option (A) is not correct.
Option (B) is correct.
Option (C) is not correct.
Option (D) is not correct.
Learn more:
1. Learn more about inverse of the functionhttps://brainly.com/question/1632445.
2. Learn more about equation of circle brainly.com/question/1506955.
3. Learn more about range and domain of the function brainly.com/question/3412497
Answer details:
Grade: High School
Subject: Mathematics
Chapter: Trigonometry
Keywords: length of the leg, triangle, isosceles,perpendicular bisectors, sides, right angle triangle, triangle, altitudes, hypotenuse, on the triangle, hypotenuse, trigonometric functions, Pythagoras theorem, formula.