Question

In the right triangle shown, DF=EF=3. How long is DE

Answer 1

`DE=3√(2)\ units`

Explanation:

see the attached figure to better understand the problem

In this problem we have an isosceles right triangle (because has two equal sides)

so

Applying the Pythagorean theorem

`DE^2=DF^2+EF^2`

substitute the given values

`DE^2=3^2+3^2`

`DE^2=18\\DE=3√(2)\ units`