Answer:
B) Hypotenuse = Leg ∙ √2
Explanation:
This is a well-known ratio in the 45-45-90 right triangle, but we can derive it.
An isosceles right triangle has two congruent legs forming the right angle and the hypotenuse opposite the right angle. The Pythagorean theorem works since it is a right angle.
Normally, the legs are a and b, and the hypotenuse is c, and we have
a^2 + b^2 = c^2
Here the legs are congruent, so we have a = b.
Substituting a for b, we have
a^2 + a^2 = c^2
2a^2 = c^2
c^2 = 2a^2
c = a√2
Answer: B) Hypotenuse = Leg ∙ √2