Isosceles and equilateral triangles

Examples0/5 watched

0/5

Now Playing:Isosceles and equilateral triangles – Example 1a

Find x.
In $\triangle DEF$ , $\overline {EY}$ is a perpendicular line to $\overline {DF}$ and $Y$ is the midpoint of $\overline {DF}$ . Why is $\triangle DEF$ an isosceles triangle? Show your reasoning.

No Javascript

It looks like you have javascript disabled.

You can still navigate around the site and check out our free content, but some functionality, such as sign up, will not work.

If you do have javascript enabled there may have been a loading error; try refreshing your browser.