moon moon
The helps look like this.

The fully labeled sketch could look like this:

Complete it by adding a red line between the height hk and the slant height hs to form a right-angled triangle!

If you're still having trouble setting up the Pythagorean Theorem, take a look at the following YouTube video:

This help is locked by a code.
Your teacher will give it to you.

The following intermediate step may help you:

Voice messages can either be recorded directly on the website or you can upload your own audios:

 

Using an iFrame, you can embed various contents from other websites, such as GeoGebra with its functionality. Try out the slider!